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%% Cell type:markdown id:94154e6c tags:
# Announcements - Monday
* Download files for today's lecture
* [Exam 1 Conflict Form](https://docs.google.com/forms/d/e/1FAIpQLScKmey733tOjLfJ2q13Np76w_4o6cFcGVyNqWZmseZH0KNp2w/viewform)
* General: Wednesday February 22: 5:45 pm
* McBurney: Wednesday Februrary 22 5:30 pm - If you are approved for anything other than extra time and small group testing please fill out the form
* Alternate: Thursday February 23 5:45 pm
* Location will be sent by email on Monday February 20
* Note: Chemistry has an exam at the same time as our Wednesday exam
* Note: Wednesday Evening section
- alternate time 7:30 - 9:00 pm
- please fill out the conflict form to get on the list for the location email
- feel free to revise your conflict form if this time works better for you
* [The best way to study for the exam!!!](https://git.doit.wisc.edu/cdis/cs/courses/cs220/cs220-lecture-material/-/tree/main/s23/old_exams/exam1)
%% Cell type:markdown id:fcdba72c tags: %% Cell type:markdown id:fcdba72c tags:
# Conditionals 2 # Conditionals 2
## Readings ## Readings
- Parts of Chapter 5 of Think Python - Parts of Chapter 5 of Think Python
- Chapter 4.6 to end (skip 4.7) of Python for Everybody - Chapter 4.6 to end (skip 4.7) of Python for Everybody
%% Cell type:markdown id:5d944b30 tags: %% Cell type:markdown id:5d944b30 tags:
## Learning Objectives ## Learning Objectives
- Read and write nested conditional statements - Read and write nested conditional statements
- Define, state reasons for, and provide examples of refactoring - Define, state reasons for, and provide examples of refactoring
- Refactor code containing conditional statements into boolean expressions - Refactor code containing conditional statements into boolean expressions
%% Cell type:markdown id:cc7d8729 tags: %% Cell type:markdown id:cc7d8729 tags:
### Warmup ### Warmup
%% Cell type:markdown id:ab5912f2 tags: %% Cell type:markdown id:ab5912f2 tags:
What's wrong with this code? What's wrong with this code?
%% Cell type:code id:ececa83c tags: %% Cell type:code id:ececa83c tags:
``` python ``` python
team = "Badgers" team = "Badgers"
# if team == "Gophers" or "Hawkeyes" or "Spartans": # code with bug # if team == "Gophers" or "Hawkeyes" or "Spartans": # code with bug
if team == "Gophers" or team == "Hawkeyes" or team == "Spartans": if team == "Gophers" or team == "Hawkeyes" or team == "Spartans":
# fix: problem == has higher precedence than "or" # fix: problem == has higher precedence than "or"
# conditions should always be written with expansions # conditions should always be written with expansions
print("Ahh no badgers!") print("Ahh no badgers!")
else: else:
print("Yay, go badgers!") print("Yay, go badgers!")
``` ```
%% Output %% Output
Yay, go badgers! Yay, go badgers!
%% Cell type:markdown id:0f207c28 tags: %% Cell type:markdown id:0f207c28 tags:
**Find a partner to do these TODOs** **Find a partner to do these TODOs**
TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values. TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values.
TODO: fix the expression after your experiments TODO: fix the expression after your experiments
%% Cell type:code id:30bb2225 tags: %% Cell type:code id:30bb2225 tags:
``` python ``` python
team = "Badgers" team = "Badgers"
print(team == "Gophers" or "Hawkeyes" or "Spartans") print(team == "Gophers" or "Hawkeyes" or "Spartans")
``` ```
%% Output %% Output
Hawkeyes Hawkeyes
%% Cell type:code id:277df345 tags: %% Cell type:code id:277df345 tags:
``` python ``` python
team = "Gophers" team = "Gophers"
print(team == "Gophers" or "Hawkeyes" or "Spartans") print(team == "Gophers" or "Hawkeyes" or "Spartans")
``` ```
%% Output %% Output
True True
%% Cell type:markdown id:beeb3adf tags: %% Cell type:markdown id:beeb3adf tags:
## Example 1: Classifying Children by Age ## Example 1: Classifying Children by Age
- Chained conditionals: - Chained conditionals:
- multiple branch within the same conditional - multiple branch within the same conditional
- connected conditions - connected conditions
- if conditional branch - if conditional branch
- elif subjective conditional branch(es) - elif subjective conditional branch(es)
- elif conditions are subjective to the if condition - elif conditions are subjective to the if condition
- that is, only when if condition evaluates to `False`, the next elif condition is evaluated - that is, only when if condition evaluates to `False`, the next elif condition is evaluated
- only when the first elif condition evaluates to `False`, the second elif condition is evaluated - only when the first elif condition evaluates to `False`, the second elif condition is evaluated
- and so on ... - and so on ...
- else alternate branch - else alternate branch
Age classification: Age classification:
- "baby" 0 to 1 - "baby" 0 to 1
- "toddler" 2 to 3 - "toddler" 2 to 3
- "kid" 4 to 10 - "kid" 4 to 10
- "tween" 11 to 12 - "tween" 11 to 12
- "teen" 13 to 17 - "teen" 13 to 17
- "adult" 18+ (alternate execution) - "adult" 18+ (alternate execution)
%% Cell type:code id:1cec8460 tags: %% Cell type:code id:1cec8460 tags:
``` python ``` python
age = int(input("Enter your age: ")) age = int(input("Enter your age: "))
def categorize_age(age): def categorize_age(age):
if 0 <= age <= 1: if 0 <= age <= 1:
return "infant" return "infant"
elif 2 <= age <= 3: elif 2 <= age <= 3:
return "toddler" return "toddler"
elif 4 <= age <= 10: elif 4 <= age <= 10:
return "kid" return "kid"
elif 11 <= age <= 12: elif 11 <= age <= 12:
return "tween" return "tween"
elif 13 <= age <= 17: elif 13 <= age <= 17:
return "teen" return "teen"
else: else:
return "adult" return "adult"
print("You are a:", categorize_age(age)) print("You are a:", categorize_age(age))
``` ```
%% Output %% Output
Enter your age: 10 Enter your age: 10
You are a: kid You are a: kid
%% Cell type:markdown id:8fd63040 tags: %% Cell type:markdown id:8fd63040 tags:
## Example 2: Date Printer ## Example 2: Date Printer
- converts 2/14/2022 to "Feb 14th of ‘22" - converts 2/14/2022 to "Feb 14th of ‘22"
- decompose a big problem into appropriate steps, by writing functions for individual components - decompose a big problem into appropriate steps, by writing functions for individual components
%% Cell type:code id:7c72488a tags: %% Cell type:code id:7c72488a tags:
``` python ``` python
def format_month(month): def format_month(month):
"""Convert a month (as an integer) into a string. """Convert a month (as an integer) into a string.
1 is Jan, 2 is Feb, etc.""" 1 is Jan, 2 is Feb, etc."""
if month == 1: if month == 1:
return "Jan" return "Jan"
elif month == 2: elif month == 2:
return "Feb" return "Feb"
elif month == 3: elif month == 3:
return "Mar" return "Mar"
elif month == 4: elif month == 4:
return "Apr" return "Apr"
elif month == 5: elif month == 5:
return "May" return "May"
elif month == 6: elif month == 6:
return "Jun" return "Jun"
elif month == 7: elif month == 7:
return "Jul" return "Jul"
elif month == 8: elif month == 8:
return "Aug" return "Aug"
elif month == 9: elif month == 9:
return "Sep" return "Sep"
elif month == 10: elif month == 10:
return "Oct" return "Oct"
elif month == 11: elif month == 11:
return "Nov" return "Nov"
elif month == 12: elif month == 12:
return "Dec" return "Dec"
else: else:
return "Invalid month!" return "Invalid month!"
``` ```
%% Cell type:code id:71bf7f2d tags: %% Cell type:code id:71bf7f2d tags:
``` python ``` python
def format_day(day): def format_day(day):
"""Covert a day into a date string with proper ending. """Covert a day into a date string with proper ending.
16 --> '16th', 23 --> '23rd', """ 16 --> '16th', 23 --> '23rd', """
suffix = "" suffix = ""
if day < 1: if day < 1:
suffix = "error" suffix = "error"
elif 11 <= day % 100 <= 20: elif 11 <= day % 100 <= 20:
suffix = str(day) + "th" suffix = str(day) + "th"
elif day % 10 == 1: elif day % 10 == 1:
suffix = str(day) + "st" suffix = str(day) + "st"
elif day % 10 == 2: elif day % 10 == 2:
suffix = str(day) + "nd" suffix = str(day) + "nd"
elif day % 10 == 3: elif day % 10 == 3:
suffix = str(day) + "rd" suffix = str(day) + "rd"
else: else:
suffix = str(day) + "th" suffix = str(day) + "th"
return suffix return suffix
print(format_day(1)) print(format_day(1))
print(format_day(2)) print(format_day(2))
print(format_day(3)) print(format_day(3))
print(format_day(11)) print(format_day(11))
print(format_day(21)) print(format_day(21))
print(format_day(111)) print(format_day(111))
print(format_day(-1)) print(format_day(-1))
``` ```
%% Output %% Output
1st 1st
2nd 2nd
3rd 3rd
11th 11th
21st 21st
111th 111th
error error
%% Cell type:code id:c142acc7 tags: %% Cell type:code id:c142acc7 tags:
``` python ``` python
def format_date(month, day, year): def format_date(month, day, year):
"""returns a string representing the date, such as Feb 11th of ‘22""" """returns a string representing the date, such as Feb 11th of ‘22"""
result_str = "" result_str = ""
result_str += format_month(month) result_str += format_month(month)
result_str += " " + format_day(day) result_str += " " + format_day(day)
result_str += " of '" + str(year % 100) result_str += " of '" + str(year % 100)
return result_str return result_str
``` ```
%% Cell type:code id:e45d4fd3 tags: %% Cell type:code id:e45d4fd3 tags:
``` python ``` python
format_date(9, 26, 2022) format_date(9, 26, 2022)
``` ```
%% Output %% Output
"Sep 26th of '22" "Sep 26th of '22"
%% Cell type:markdown id:efc4659c tags: %% Cell type:markdown id:efc4659c tags:
## Example 3: Stoplight ## Example 3: Stoplight
<div> <div>
<img src="attachment:Stoplight.png" width="600"/> <img src="attachment:Stoplight.png" width="600"/>
</div> </div>
%% Cell type:code id:fc1cec93 tags: %% Cell type:code id:fc1cec93 tags:
``` python ``` python
def stop_light(color, distance): def stop_light(color, distance):
if color == 'red': if color == 'red':
if distance < 15: if distance < 15:
return "hit the gas" return "hit the gas"
else: else:
return "stop abruptly" return "stop abruptly"
elif color == 'yellow': elif color == 'yellow':
if distance < 30: if distance < 30:
return "continue at same speed" return "continue at same speed"
else: else:
return "stop" return "stop"
elif color == "green": elif color == "green":
return "smile :)" return "smile :)"
else: else:
return "Invalid color!" return "Invalid color!"
``` ```
%% Cell type:markdown id:6fd52715 tags: %% Cell type:markdown id:6fd52715 tags:
## Refactoring ## Refactoring
What is it? What is it?
- Improving/rewriting parts of a program without changing its behavior. - Improving/rewriting parts of a program without changing its behavior.
- Like a re-wording of a recipe without changing it - Like a re-wording of a recipe without changing it
Why do it? Why do it?
- Make it easier to read and understand the code & what it's doing - Make it easier to read and understand the code & what it's doing
- Sometimes to make code run faster - Sometimes to make code run faster
Principles of good refactoring: Principles of good refactoring:
- Don't change the program's behavior! - Don't change the program's behavior!
- The program should end up more readable than it started - The program should end up more readable than it started
- Use knowledge of if/else, and/or/not, ==, !=, etc. - Use knowledge of if/else, and/or/not, ==, !=, etc.
%% Cell type:markdown id:b5ad668e tags: %% Cell type:markdown id:b5ad668e tags:
### Refactoring example 1: nested if conditions ### Refactoring example 1: nested if conditions
%% Cell type:code id:d391cc8a tags: %% Cell type:code id:d391cc8a tags:
``` python ``` python
# check combination of a lock # check combination of a lock
def check_combination(a, b, c): def check_combination(a, b, c):
if a == 2: if a == 2:
if b == 2: if b == 2:
if c == 0: if c == 0:
return True return True
else: else:
return False return False
else: else:
return False return False
else: else:
return False return False
print(check_combination(2, 2, 0)) print(check_combination(2, 2, 0))
print(check_combination(2, 1, 0)) print(check_combination(2, 1, 0))
print(check_combination(1, 2, 0)) print(check_combination(1, 2, 0))
print(check_combination(3, 1, 9)) print(check_combination(3, 1, 9))
``` ```
%% Output %% Output
True True
False False
False False
False False
%% Cell type:code id:e5caed75 tags: %% Cell type:code id:e5caed75 tags:
``` python ``` python
def bad_combo(a, b, c): def bad_combo(a, b, c):
return a == 2 or b == 2 or c == 0 return a == 2 or b == 2 or c == 0
print(bad_combo(2, 2, 0)) print(bad_combo(2, 2, 0))
print(bad_combo(2, 1, 0)) print(bad_combo(2, 1, 0))
print(bad_combo(1, 2, 0)) print(bad_combo(1, 2, 0))
print(bad_combo(3, 1, 9)) print(bad_combo(3, 1, 9))
``` ```
%% Output %% Output
True True
True True
True True
False False
%% Cell type:code id:b69cadc1 tags: %% Cell type:code id:b69cadc1 tags:
``` python ``` python
def refactor_combo(a, b, c): def refactor_combo(a, b, c):
return a == 2 and b == 2 and c == 0 return a == 2 and b == 2 and c == 0
print(refactor_combo(2, 2, 0)) print(refactor_combo(2, 2, 0))
print(refactor_combo(2, 1, 0)) print(refactor_combo(2, 1, 0))
print(refactor_combo(1, 2, 0)) print(refactor_combo(1, 2, 0))
print(refactor_combo(3, 1, 9)) print(refactor_combo(3, 1, 9))
``` ```
%% Output %% Output
True True
False False
False False
False False
%% Cell type:markdown id:ef5852ea tags: %% Cell type:markdown id:ef5852ea tags:
### Refactoring example 2: cluttered conditional ### Refactoring example 2: cluttered conditional
%% Cell type:code id:9e45e8f8 tags: %% Cell type:code id:9e45e8f8 tags:
``` python ``` python
def check_different(b1, b2): def check_different(b1, b2):
if b1 == True and b2 == False: if b1 == True and b2 == False:
return True return True
elif b1 == False and b2 == True: elif b1 == False and b2 == True:
return True return True
elif b1 == True and b2 == True: elif b1 == True and b2 == True:
return False return False
elif b1 == False and b2 == False: elif b1 == False and b2 == False:
return False return False
print(check_different(True, False)) print(check_different(True, False))
print(check_different(False, False)) print(check_different(False, False))
print(check_different(False, True)) print(check_different(False, True))
print(check_different(True, True)) print(check_different(True, True))
``` ```
%% Output %% Output
True True
False False
True True
False False
%% Cell type:code id:7b625604 tags: %% Cell type:code id:7b625604 tags:
``` python ``` python
def refactor_check_different(b1, b2): def refactor_check_different(b1, b2):
return b1 != b2 return b1 != b2
print(refactor_check_different(True, False)) print(refactor_check_different(True, False))
print(refactor_check_different(False, False)) print(refactor_check_different(False, False))
print(refactor_check_different(False, True)) print(refactor_check_different(False, True))
print(refactor_check_different(True, True)) print(refactor_check_different(True, True))
``` ```
%% Output %% Output
True True
False False
True True
False False
%% Cell type:markdown id:a488bc9c tags: %% Cell type:markdown id:a488bc9c tags:
## After lecture ## After lecture
- go through examples in slides - go through examples in slides
- reason about every refactor version and predict correctness of the refactor - reason about every refactor version and predict correctness of the refactor
- try out each refactor example using Interactive Exercises - try out each refactor example using Interactive Exercises
- try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output) - try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output)
%% Cell type:code id:2ba3bbcc tags: %% Cell type:code id:2ba3bbcc tags:
``` python ``` python
# Refactoring Practice 1: recognizing equivalent code # Refactoring Practice 1: recognizing equivalent code
# Exam 1 Fall 2020 # Exam 1 Fall 2020
def g(x, y): def g(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
if y: if y:
return True return True
else: else:
return False return False
else: else:
return False return False
# TODO: try all combinations of intitializations to b1 and b2 # TODO: try all combinations of intitializations to b1 and b2
b1 = True b1 = True
b2 = True b2 = True
g(b1, b2) g(b1, b2)
# Which of the following will give the same result in all cases, as g(b1, b2)? # Which of the following will give the same result in all cases, as g(b1, b2)?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) b1 or b2 # d.) b1 or b2
``` ```
%% Output %% Output
True True
%% Cell type:code id:d4a4d099 tags: %% Cell type:code id:d4a4d099 tags:
``` python ``` python
# Refactoring Practice 2: # Refactoring Practice 2:
def h(x, y): def h(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return False return False
else: else:
if y: if y:
return False return False
else: else:
return True return True
# TODO: try all combinations of intitializations to b1 and b2 # TODO: try all combinations of intitializations to b1 and b2
b1 = True b1 = True
b2 = True b2 = True
h(b1, b2) h(b1, b2)
# Which of the following will give the same result in all cases, as h(b1, b2) ? # Which of the following will give the same result in all cases, as h(b1, b2) ?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) not b1 and not b2 # d.) not b1 and not b2
``` ```
%% Output %% Output
False False
%% Cell type:code id:0d2cfee6 tags: %% Cell type:code id:0d2cfee6 tags:
``` python ``` python
# Refactoring Practice 3: # Refactoring Practice 3:
def some_bool_eval(x, y): def some_bool_eval(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return True return True
elif y: elif y:
return True return True
else: else:
return False return False
print(some_bool_eval(True, False)) print(some_bool_eval(True, False))
print(some_bool_eval(False, True)) print(some_bool_eval(False, True))
print(some_bool_eval(True, True)) print(some_bool_eval(True, True))
print(some_bool_eval(False, False)) print(some_bool_eval(False, False))
# what is the best way to refactor the body of the function ? # what is the best way to refactor the body of the function ?
# A. return x and y # A. return x and y
# B. return x or y # B. return x or y
# C. return x != y # C. return x != y
# D. return x == y # D. return x == y
``` ```
%% Output %% Output
True True
True True
True True
False False
......
s23/Gurmail_lecture_notes/09_Conditionals-2/lec_09_Conditionals_2_template_Gurmail_lec1.ipynb
+ 22
− 1
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%% Cell type:markdown id:53aab2e8 tags:
# Announcements - Monday
* Download files for today's lecture
* [Exam 1 Conflict Form](https://docs.google.com/forms/d/e/1FAIpQLScKmey733tOjLfJ2q13Np76w_4o6cFcGVyNqWZmseZH0KNp2w/viewform)
* General: Wednesday February 22: 5:45 pm
* McBurney: Wednesday Februrary 22 5:30 pm - If you are approved for anything other than extra time and small group testing please fill out the form
* Alternate: Thursday February 23 5:45 pm
* Location will be sent by email on Monday February 20
* Note: Chemistry has an exam at the same time as our Wednesday exam
* Note: Wednesday Evening section
- alternate time 7:30 - 9:00 pm
- please fill out the conflict form to get on the list for the location email
- feel free to revise your conflict form if this time works better for you
* [The best way to study for the exam!!!](https://git.doit.wisc.edu/cdis/cs/courses/cs220/cs220-lecture-material/-/tree/main/s23/old_exams/exam1)
%% Cell type:markdown id:25751b55 tags: %% Cell type:markdown id:25751b55 tags:
# Conditionals 2 # Conditionals 2
## Readings ## Readings
- Parts of Chapter 5 of Think Python - Parts of Chapter 5 of Think Python
- Chapter 4.6 to end (skip 4.7) of Python for Everybody - Chapter 4.6 to end (skip 4.7) of Python for Everybody
%% Cell type:markdown id:d29fedb7 tags: %% Cell type:markdown id:d29fedb7 tags:
## Learning Objectives ## Learning Objectives
- Read and write nested conditional statements - Read and write nested conditional statements
- Define, state reasons for, and provide examples of refactoring - Define, state reasons for, and provide examples of refactoring
- Refactor code containing conditional statements into boolean expressions - Refactor code containing conditional statements into boolean expressions
%% Cell type:markdown id:00a02ca4 tags: %% Cell type:markdown id:00a02ca4 tags:
### Warmup ### Warmup
%% Cell type:markdown id:4058219f tags: %% Cell type:markdown id:4058219f tags:
What's wrong with this code? What's wrong with this code?
%% Cell type:code id:909ef1b6 tags: %% Cell type:code id:909ef1b6 tags:
``` python ``` python
team = "Badgers" team = "Badgers"
if team == "Gophers" or "Hawkeyes" or "Spartans": if team == "Gophers" or "Hawkeyes" or "Spartans":
print("Ahh no badgers!") print("Ahh no badgers!")
else: else:
print("Yay, go badgers!") print("Yay, go badgers!")
``` ```
%% Cell type:markdown id:a9579e28 tags: %% Cell type:markdown id:a9579e28 tags:
**Find a partner to do these TODOs** **Find a partner to do these TODOs**
TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values. Observe what is wrong with the current expression. TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values. Observe what is wrong with the current expression.
TODO: fix the expression after your experiments TODO: fix the expression after your experiments
%% Cell type:markdown id:dc60b188 tags: %% Cell type:markdown id:dc60b188 tags:
## Example 1: Classifying Children by Age ## Example 1: Classifying Children by Age
- Chained conditionals: - Chained conditionals:
- multiple branch within the same conditional - multiple branch within the same conditional
- connected conditions - connected conditions
- if conditional branch - if conditional branch
- elif subjective conditional branch(es) - elif subjective conditional branch(es)
- elif conditions are subjective to the if condition - elif conditions are subjective to the if condition
- that is, only when if condition evaluates to `False`, the next elif condition is evaluated - that is, only when if condition evaluates to `False`, the next elif condition is evaluated
- only when the first elif condition evaluates to `False`, the second elif condition is evaluated - only when the first elif condition evaluates to `False`, the second elif condition is evaluated
- and so on ... - and so on ...
- else alternate branch - else alternate branch
Age classification: Age classification:
- "baby" 0 to 1 - "baby" 0 to 1
- "toddler" 2 to 3 - "toddler" 2 to 3
- "kid" 4 to 10 - "kid" 4 to 10
- "tween" 11 to 12 - "tween" 11 to 12
- "teen" 13 to 17 - "teen" 13 to 17
- "adult" 18+ (alternate execution) - "adult" 18+ (alternate execution)
%% Cell type:code id:2ff08fe4 tags: %% Cell type:code id:2ff08fe4 tags:
``` python ``` python
# TODO: get age as user input # TODO: get age as user input
age = int(input("Enter your age: ")) age = int(input("Enter your age: "))
def categorize_age(age): def categorize_age(age):
if 0 <= age <= 1: if 0 <= age <= 1:
return "infant" # TODO: discuss why we have a return here instead of print return "infant" # TODO: discuss why we have a return here instead of print
elif 2 <= age <= 3: elif 2 <= age <= 3:
return "toddler" return "toddler"
elif 4 <= age <= 10: elif 4 <= age <= 10:
return "kid" return "kid"
elif 11 <= age <= 12: elif 11 <= age <= 12:
return "tween" return "tween"
elif 13 <= age <= 17: elif 13 <= age <= 17:
return "teen" return "teen"
else: else:
return "adult" return "adult"
print("You are a:", categorize_age(age)) print("You are a:", categorize_age(age))
``` ```
%% Cell type:markdown id:def170db tags: %% Cell type:markdown id:def170db tags:
## Example 2: Date Printer ## Example 2: Date Printer
- converts 2/14/2022 to "Feb 14th of ‘22" - converts 2/14/2022 to "Feb 14th of ‘22"
- decompose a big problem into appropriate steps, by writing functions for individual components - decompose a big problem into appropriate steps, by writing functions for individual components
%% Cell type:code id:8c627afc tags: %% Cell type:code id:8c627afc tags:
``` python ``` python
def format_month(month): def format_month(month):
"""Convert a month (as an integer) into a string. """Convert a month (as an integer) into a string.
1 is Jan, 2 is Feb, etc.""" 1 is Jan, 2 is Feb, etc."""
pass pass
``` ```
%% Cell type:code id:4207cb50 tags: %% Cell type:code id:4207cb50 tags:
``` python ``` python
def format_day(day): def format_day(day):
"""Covert a day into a date string with proper ending. """Covert a day into a date string with proper ending.
16 --> '16th', 23 --> '23rd', """ 16 --> '16th', 23 --> '23rd', """
suffix = "" suffix = ""
# TODO: write the conditional here # TODO: write the conditional here
return suffix return suffix
print(format_day(1)) print(format_day(1))
print(format_day(2)) print(format_day(2))
print(format_day(3)) print(format_day(3))
print(format_day(11)) print(format_day(11))
print(format_day(21)) print(format_day(21))
print(format_day(111)) print(format_day(111))
print(format_day(-1)) print(format_day(-1))
``` ```
%% Cell type:code id:918b726c tags: %% Cell type:code id:918b726c tags:
``` python ``` python
def format_date(month, day, year): def format_date(month, day, year):
"""returns a string representing the date, such as Feb 11th of ‘22""" """returns a string representing the date, such as Feb 11th of ‘22"""
pass pass
``` ```
%% Cell type:code id:92cde74e tags: %% Cell type:code id:92cde74e tags:
``` python ``` python
format_date(2, 14, 2022) format_date(2, 14, 2022)
``` ```
%% Cell type:markdown id:528d781f tags: %% Cell type:markdown id:528d781f tags:
## Example 3: Stoplight ## Example 3: Stoplight
<div> <div>
<img src="attachment:Stoplight.png" width="600"/> <img src="attachment:Stoplight.png" width="600"/>
</div> </div>
%% Cell type:code id:3c0c3bcd tags: %% Cell type:code id:3c0c3bcd tags:
``` python ``` python
def stop_light(color, distance): def stop_light(color, distance):
pass pass
``` ```
%% Cell type:markdown id:459296f2 tags: %% Cell type:markdown id:459296f2 tags:
## Refactoring ## Refactoring
What is it? What is it?
- Improving/rewriting parts of a program without changing its behavior. - Improving/rewriting parts of a program without changing its behavior.
- Like a re-wording of a recipe without changing it - Like a re-wording of a recipe without changing it
Why do it? Why do it?
- Make it easier to read and understand the code & what it's doing - Make it easier to read and understand the code & what it's doing
- Sometimes to make code run faster - Sometimes to make code run faster
Principles of good refactoring: Principles of good refactoring:
- Don't change the program's behavior! - Don't change the program's behavior!
- The program should end up more readable than it started - The program should end up more readable than it started
- Use knowledge of if/else, and/or/not, ==, !=, etc. - Use knowledge of if/else, and/or/not, ==, !=, etc.
%% Cell type:markdown id:d5aae7eb tags: %% Cell type:markdown id:d5aae7eb tags:
### Refactoring example 1: nested if conditions ### Refactoring example 1: nested if conditions
%% Cell type:code id:d03bc22e tags: %% Cell type:code id:d03bc22e tags:
``` python ``` python
# check combination of a lock # check combination of a lock
def check_combination(a, b, c): def check_combination(a, b, c):
if a == 2: if a == 2:
if b == 2: if b == 2:
if c == 0: if c == 0:
return True return True
else: else:
return False return False
else: else:
return False return False
else: else:
return False return False
print(check_combination(2, 2, 0)) print(check_combination(2, 2, 0))
print(check_combination(2, 1, 0)) print(check_combination(2, 1, 0))
print(check_combination(1, 2, 0)) print(check_combination(1, 2, 0))
print(check_combination(3, 1, 9)) print(check_combination(3, 1, 9))
``` ```
%% Cell type:code id:feddb4b9 tags: %% Cell type:code id:feddb4b9 tags:
``` python ``` python
def bad_combo(a, b, c): def bad_combo(a, b, c):
pass pass
print(bad_combo(2, 2, 0)) print(bad_combo(2, 2, 0))
print(bad_combo(2, 1, 0)) print(bad_combo(2, 1, 0))
print(bad_combo(1, 2, 0)) print(bad_combo(1, 2, 0))
print(bad_combo(3, 1, 9)) print(bad_combo(3, 1, 9))
``` ```
%% Cell type:code id:b30eed5f tags: %% Cell type:code id:b30eed5f tags:
``` python ``` python
def refactor_combo(a, b, c): def refactor_combo(a, b, c):
pass pass
print(refactor_combo(2, 2, 0)) print(refactor_combo(2, 2, 0))
print(refactor_combo(2, 1, 0)) print(refactor_combo(2, 1, 0))
print(refactor_combo(1, 2, 0)) print(refactor_combo(1, 2, 0))
print(refactor_combo(3, 1, 9)) print(refactor_combo(3, 1, 9))
``` ```
%% Cell type:markdown id:8b7f186f tags: %% Cell type:markdown id:8b7f186f tags:
### Refactoring example 2: cluttered conditional ### Refactoring example 2: cluttered conditional
%% Cell type:code id:5285840d tags: %% Cell type:code id:5285840d tags:
``` python ``` python
def check_different(b1, b2): def check_different(b1, b2):
if b1 == True and b2 == False: if b1 == True and b2 == False:
return True return True
elif b1 == False and b2 == True: elif b1 == False and b2 == True:
return True return True
elif b1 == True and b2 == True: elif b1 == True and b2 == True:
return False return False
elif b1 == False and b2 == False: elif b1 == False and b2 == False:
return False return False
print(check_different(True, False)) print(check_different(True, False))
print(check_different(False, False)) print(check_different(False, False))
print(check_different(False, True)) print(check_different(False, True))
print(check_different(True, True)) print(check_different(True, True))
``` ```
%% Cell type:code id:e53c2cfe tags: %% Cell type:code id:e53c2cfe tags:
``` python ``` python
def refactor_check_different(b1, b2): def refactor_check_different(b1, b2):
pass pass
print(refactor_check_different(True, False)) print(refactor_check_different(True, False))
print(refactor_check_different(False, False)) print(refactor_check_different(False, False))
print(refactor_check_different(False, True)) print(refactor_check_different(False, True))
print(refactor_check_different(True, True)) print(refactor_check_different(True, True))
``` ```
%% Cell type:markdown id:5dba6585 tags: %% Cell type:markdown id:5dba6585 tags:
## After lecture ## After lecture
- go through examples in slides - go through examples in slides
- reason about every refactor version and predict correctness of the refactor - reason about every refactor version and predict correctness of the refactor
- try out each refactor example using Interactive Exercises - try out each refactor example using Interactive Exercises
- try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output) - try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output)
%% Cell type:code id:80c45d13 tags: %% Cell type:code id:80c45d13 tags:
``` python ``` python
# Refactoring Practice 1: recognizing equivalent code # Refactoring Practice 1: recognizing equivalent code
# Exam 1 Fall 2020 # Exam 1 Fall 2020
def g(x, y): def g(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
if y: if y:
return True return True
else: else:
return False return False
else: else:
return False return False
# Which of the following will give the same result in all cases, as g(b1, b2)? # Which of the following will give the same result in all cases, as g(b1, b2)?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) b1 or b2 # d.) b1 or b2
``` ```
%% Cell type:code id:795e83e4 tags: %% Cell type:code id:795e83e4 tags:
``` python ``` python
# Refactoring Practice 2: # Refactoring Practice 2:
def h(x, y): def h(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return False return False
else: else:
if y: if y:
return False return False
else: else:
return True return True
# Which of the following will give the same result in all cases, as h(b1, b2) ? # Which of the following will give the same result in all cases, as h(b1, b2) ?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) not b1 and not b2 # d.) not b1 and not b2
``` ```
%% Cell type:code id:6fca19ec tags: %% Cell type:code id:6fca19ec tags:
``` python ``` python
# Refactoring Practice 3: # Refactoring Practice 3:
def some_bool_eval(x, y): def some_bool_eval(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return True return True
elif y: elif y:
return True return True
else: else:
return False return False
print(some_bool_eval(True, False)) print(some_bool_eval(True, False))
print(some_bool_eval(False, True)) print(some_bool_eval(False, True))
print(some_bool_eval(True, True)) print(some_bool_eval(True, True))
print(some_bool_eval(False, False)) print(some_bool_eval(False, False))
# what is the best way to refactor the body of the function ? # what is the best way to refactor the body of the function ?
# A. return x and y # A. return x and y
# B. return x or y # B. return x or y
# C. return x != y # C. return x != y
# D. return x == y # D. return x == y
``` ```
......
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%% Cell type:markdown id:4a88ba18 tags:
# Announcements - Monday
* Download files for today's lecture
* [Exam 1 Conflict Form](https://docs.google.com/forms/d/e/1FAIpQLScKmey733tOjLfJ2q13Np76w_4o6cFcGVyNqWZmseZH0KNp2w/viewform)
* General: Wednesday February 22: 5:45 pm
* McBurney: Wednesday Februrary 22 5:30 pm - If you are approved for anything other than extra time and small group testing please fill out the form
* Alternate: Thursday February 23 5:45 pm
* Location will be sent by email on Monday February 20
* Note: Chemistry has an exam at the same time as our Wednesday exam
* Note: Wednesday Evening section
- alternate time 7:30 - 9:00 pm
- please fill out the conflict form to get on the list for the location email
- feel free to revise your conflict form if this time works better for you
* [The best way to study for the exam!!!](https://git.doit.wisc.edu/cdis/cs/courses/cs220/cs220-lecture-material/-/tree/main/s23/old_exams/exam1)
%% Cell type:markdown id:25751b55 tags: %% Cell type:markdown id:25751b55 tags:
# Conditionals 2 # Conditionals 2
## Readings ## Readings
- Parts of Chapter 5 of Think Python - Parts of Chapter 5 of Think Python
- Chapter 4.6 to end (skip 4.7) of Python for Everybody - Chapter 4.6 to end (skip 4.7) of Python for Everybody
%% Cell type:markdown id:d29fedb7 tags: %% Cell type:markdown id:d29fedb7 tags:
## Learning Objectives ## Learning Objectives
- Read and write nested conditional statements - Read and write nested conditional statements
- Define, state reasons for, and provide examples of refactoring - Define, state reasons for, and provide examples of refactoring
- Refactor code containing conditional statements into boolean expressions - Refactor code containing conditional statements into boolean expressions
%% Cell type:markdown id:00a02ca4 tags: %% Cell type:markdown id:00a02ca4 tags:
### Warmup ### Warmup
%% Cell type:markdown id:4058219f tags: %% Cell type:markdown id:4058219f tags:
What's wrong with this code? What's wrong with this code?
%% Cell type:code id:909ef1b6 tags: %% Cell type:code id:909ef1b6 tags:
``` python ``` python
team = "Badgers" team = "Badgers"
if team == "Gophers" or "Hawkeyes" or "Spartans": if team == "Gophers" or "Hawkeyes" or "Spartans":
print("Ahh no badgers!") print("Ahh no badgers!")
else: else:
print("Yay, go badgers!") print("Yay, go badgers!")
``` ```
%% Cell type:markdown id:a9579e28 tags: %% Cell type:markdown id:a9579e28 tags:
**Find a partner to do these TODOs** **Find a partner to do these TODOs**
TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values. Observe what is wrong with the current expression. TODO: try to compute the boolean expression yourself, by inserting a new cell below. Change team variable's value to all three possible values. Observe what is wrong with the current expression.
TODO: fix the expression after your experiments TODO: fix the expression after your experiments
%% Cell type:markdown id:dc60b188 tags: %% Cell type:markdown id:dc60b188 tags:
## Example 1: Classifying Children by Age ## Example 1: Classifying Children by Age
- Chained conditionals: - Chained conditionals:
- multiple branch within the same conditional - multiple branch within the same conditional
- connected conditions - connected conditions
- if conditional branch - if conditional branch
- elif subjective conditional branch(es) - elif subjective conditional branch(es)
- elif conditions are subjective to the if condition - elif conditions are subjective to the if condition
- that is, only when if condition evaluates to `False`, the next elif condition is evaluated - that is, only when if condition evaluates to `False`, the next elif condition is evaluated
- only when the first elif condition evaluates to `False`, the second elif condition is evaluated - only when the first elif condition evaluates to `False`, the second elif condition is evaluated
- and so on ... - and so on ...
- else alternate branch - else alternate branch
Age classification: Age classification:
- "baby" 0 to 1 - "baby" 0 to 1
- "toddler" 2 to 3 - "toddler" 2 to 3
- "kid" 4 to 10 - "kid" 4 to 10
- "tween" 11 to 12 - "tween" 11 to 12
- "teen" 13 to 17 - "teen" 13 to 17
- "adult" 18+ (alternate execution) - "adult" 18+ (alternate execution)
%% Cell type:code id:2ff08fe4 tags: %% Cell type:code id:2ff08fe4 tags:
``` python ``` python
# TODO: get age as user input # TODO: get age as user input
age = int(input("Enter your age: ")) age = int(input("Enter your age: "))
def categorize_age(age): def categorize_age(age):
if 0 <= age <= 1: if 0 <= age <= 1:
return "infant" # TODO: discuss why we have a return here instead of print return "infant" # TODO: discuss why we have a return here instead of print
elif 2 <= age <= 3: elif 2 <= age <= 3:
return "toddler" return "toddler"
elif 4 <= age <= 10: elif 4 <= age <= 10:
return "kid" return "kid"
elif 11 <= age <= 12: elif 11 <= age <= 12:
return "tween" return "tween"
elif 13 <= age <= 17: elif 13 <= age <= 17:
return "teen" return "teen"
else: else:
return "adult" return "adult"
print("You are a:", categorize_age(age)) print("You are a:", categorize_age(age))
``` ```
%% Cell type:markdown id:def170db tags: %% Cell type:markdown id:def170db tags:
## Example 2: Date Printer ## Example 2: Date Printer
- converts 2/14/2022 to "Feb 14th of ‘22" - converts 2/14/2022 to "Feb 14th of ‘22"
- decompose a big problem into appropriate steps, by writing functions for individual components - decompose a big problem into appropriate steps, by writing functions for individual components
%% Cell type:code id:8c627afc tags: %% Cell type:code id:8c627afc tags:
``` python ``` python
def format_month(month): def format_month(month):
"""Convert a month (as an integer) into a string. """Convert a month (as an integer) into a string.
1 is Jan, 2 is Feb, etc.""" 1 is Jan, 2 is Feb, etc."""
pass pass
``` ```
%% Cell type:code id:4207cb50 tags: %% Cell type:code id:4207cb50 tags:
``` python ``` python
def format_day(day): def format_day(day):
"""Covert a day into a date string with proper ending. """Covert a day into a date string with proper ending.
16 --> '16th', 23 --> '23rd', """ 16 --> '16th', 23 --> '23rd', """
suffix = "" suffix = ""
# TODO: write the conditional here # TODO: write the conditional here
return suffix return suffix
print(format_day(1)) print(format_day(1))
print(format_day(2)) print(format_day(2))
print(format_day(3)) print(format_day(3))
print(format_day(11)) print(format_day(11))
print(format_day(21)) print(format_day(21))
print(format_day(111)) print(format_day(111))
print(format_day(-1)) print(format_day(-1))
``` ```
%% Cell type:code id:918b726c tags: %% Cell type:code id:918b726c tags:
``` python ``` python
def format_date(month, day, year): def format_date(month, day, year):
"""returns a string representing the date, such as Feb 11th of ‘22""" """returns a string representing the date, such as Feb 11th of ‘22"""
pass pass
``` ```
%% Cell type:code id:92cde74e tags: %% Cell type:code id:92cde74e tags:
``` python ``` python
format_date(2, 14, 2022) format_date(2, 14, 2022)
``` ```
%% Cell type:markdown id:528d781f tags: %% Cell type:markdown id:528d781f tags:
## Example 3: Stoplight ## Example 3: Stoplight
<div> <div>
<img src="attachment:Stoplight.png" width="600"/> <img src="attachment:Stoplight.png" width="600"/>
</div> </div>
%% Cell type:code id:3c0c3bcd tags: %% Cell type:code id:3c0c3bcd tags:
``` python ``` python
def stop_light(color, distance): def stop_light(color, distance):
pass pass
``` ```
%% Cell type:markdown id:459296f2 tags: %% Cell type:markdown id:459296f2 tags:
## Refactoring ## Refactoring
What is it? What is it?
- Improving/rewriting parts of a program without changing its behavior. - Improving/rewriting parts of a program without changing its behavior.
- Like a re-wording of a recipe without changing it - Like a re-wording of a recipe without changing it
Why do it? Why do it?
- Make it easier to read and understand the code & what it's doing - Make it easier to read and understand the code & what it's doing
- Sometimes to make code run faster - Sometimes to make code run faster
Principles of good refactoring: Principles of good refactoring:
- Don't change the program's behavior! - Don't change the program's behavior!
- The program should end up more readable than it started - The program should end up more readable than it started
- Use knowledge of if/else, and/or/not, ==, !=, etc. - Use knowledge of if/else, and/or/not, ==, !=, etc.
%% Cell type:markdown id:d5aae7eb tags: %% Cell type:markdown id:d5aae7eb tags:
### Refactoring example 1: nested if conditions ### Refactoring example 1: nested if conditions
%% Cell type:code id:d03bc22e tags: %% Cell type:code id:d03bc22e tags:
``` python ``` python
# check combination of a lock # check combination of a lock
def check_combination(a, b, c): def check_combination(a, b, c):
if a == 2: if a == 2:
if b == 2: if b == 2:
if c == 0: if c == 0:
return True return True
else: else:
return False return False
else: else:
return False return False
else: else:
return False return False
print(check_combination(2, 2, 0)) print(check_combination(2, 2, 0))
print(check_combination(2, 1, 0)) print(check_combination(2, 1, 0))
print(check_combination(1, 2, 0)) print(check_combination(1, 2, 0))
print(check_combination(3, 1, 9)) print(check_combination(3, 1, 9))
``` ```
%% Cell type:code id:feddb4b9 tags: %% Cell type:code id:feddb4b9 tags:
``` python ``` python
def bad_combo(a, b, c): def bad_combo(a, b, c):
pass pass
print(bad_combo(2, 2, 0)) print(bad_combo(2, 2, 0))
print(bad_combo(2, 1, 0)) print(bad_combo(2, 1, 0))
print(bad_combo(1, 2, 0)) print(bad_combo(1, 2, 0))
print(bad_combo(3, 1, 9)) print(bad_combo(3, 1, 9))
``` ```
%% Cell type:code id:b30eed5f tags: %% Cell type:code id:b30eed5f tags:
``` python ``` python
def refactor_combo(a, b, c): def refactor_combo(a, b, c):
pass pass
print(refactor_combo(2, 2, 0)) print(refactor_combo(2, 2, 0))
print(refactor_combo(2, 1, 0)) print(refactor_combo(2, 1, 0))
print(refactor_combo(1, 2, 0)) print(refactor_combo(1, 2, 0))
print(refactor_combo(3, 1, 9)) print(refactor_combo(3, 1, 9))
``` ```
%% Cell type:markdown id:8b7f186f tags: %% Cell type:markdown id:8b7f186f tags:
### Refactoring example 2: cluttered conditional ### Refactoring example 2: cluttered conditional
%% Cell type:code id:5285840d tags: %% Cell type:code id:5285840d tags:
``` python ``` python
def check_different(b1, b2): def check_different(b1, b2):
if b1 == True and b2 == False: if b1 == True and b2 == False:
return True return True
elif b1 == False and b2 == True: elif b1 == False and b2 == True:
return True return True
elif b1 == True and b2 == True: elif b1 == True and b2 == True:
return False return False
elif b1 == False and b2 == False: elif b1 == False and b2 == False:
return False return False
print(check_different(True, False)) print(check_different(True, False))
print(check_different(False, False)) print(check_different(False, False))
print(check_different(False, True)) print(check_different(False, True))
print(check_different(True, True)) print(check_different(True, True))
``` ```
%% Cell type:code id:e53c2cfe tags: %% Cell type:code id:e53c2cfe tags:
``` python ``` python
def refactor_check_different(b1, b2): def refactor_check_different(b1, b2):
pass pass
print(refactor_check_different(True, False)) print(refactor_check_different(True, False))
print(refactor_check_different(False, False)) print(refactor_check_different(False, False))
print(refactor_check_different(False, True)) print(refactor_check_different(False, True))
print(refactor_check_different(True, True)) print(refactor_check_different(True, True))
``` ```
%% Cell type:markdown id:5dba6585 tags: %% Cell type:markdown id:5dba6585 tags:
## After lecture ## After lecture
- go through examples in slides - go through examples in slides
- reason about every refactor version and predict correctness of the refactor - reason about every refactor version and predict correctness of the refactor
- try out each refactor example using Interactive Exercises - try out each refactor example using Interactive Exercises
- try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output) - try these sample exam questions on refactoring (predict output, then type your code and run, to confirm your output)
%% Cell type:code id:80c45d13 tags: %% Cell type:code id:80c45d13 tags:
``` python ``` python
# Refactoring Practice 1: recognizing equivalent code # Refactoring Practice 1: recognizing equivalent code
# Exam 1 Fall 2020 # Exam 1 Fall 2020
def g(x, y): def g(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
if y: if y:
return True return True
else: else:
return False return False
else: else:
return False return False
# Which of the following will give the same result in all cases, as g(b1, b2)? # Which of the following will give the same result in all cases, as g(b1, b2)?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) b1 or b2 # d.) b1 or b2
``` ```
%% Cell type:code id:795e83e4 tags: %% Cell type:code id:795e83e4 tags:
``` python ``` python
# Refactoring Practice 2: # Refactoring Practice 2:
def h(x, y): def h(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return False return False
else: else:
if y: if y:
return False return False
else: else:
return True return True
# Which of the following will give the same result in all cases, as h(b1, b2) ? # Which of the following will give the same result in all cases, as h(b1, b2) ?
# a.) b1 != b2 # a.) b1 != b2
# b.) b1 and b2 # b.) b1 and b2
# c.) b1 == b2 # c.) b1 == b2
# d.) not b1 and not b2 # d.) not b1 and not b2
``` ```
%% Cell type:code id:6fca19ec tags: %% Cell type:code id:6fca19ec tags:
``` python ``` python
# Refactoring Practice 3: # Refactoring Practice 3:
def some_bool_eval(x, y): def some_bool_eval(x, y):
# the expression after an if must be a Boolean expression or have a Boolean value # the expression after an if must be a Boolean expression or have a Boolean value
if x: if x:
return True return True
elif y: elif y:
return True return True
else: else:
return False return False
print(some_bool_eval(True, False)) print(some_bool_eval(True, False))
print(some_bool_eval(False, True)) print(some_bool_eval(False, True))
print(some_bool_eval(True, True)) print(some_bool_eval(True, True))
print(some_bool_eval(False, False)) print(some_bool_eval(False, False))
# what is the best way to refactor the body of the function ? # what is the best way to refactor the body of the function ?
# A. return x and y # A. return x and y
# B. return x or y # B. return x or y
# C. return x != y # C. return x != y
# D. return x == y # D. return x == y
``` ```
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