motivation
 - lots of online datasets
 - for download
 - available via RPC

client/server
 - IP address, port number, domain name
 - request/response

HTTP
 - https://en.wikipedia.org/wiki/Hypertext_Transfer_Protocol
 - URL
 - GET/POST/ETC
 - status codes

GET (with requests)
 - note about robots.txt file
 - pip install requests (already with Anaconda)
 - r = requests.get(URL)
 - r.status_code
 - r.raise_for_status()
 - r.text
 - r.json()

DEMO 1: web scraping

POST (with requests)
 - remote procedure calls
 - r = requests.post(URL, data={})
 - http://18.216.110.65

DEMO 2: online chat
 - read_messages
 - send_message