[Python: `with` context manager] #with #python

with.py

# https://effbot.org/zone/python-with-statement.htm
class Tyler():
    def __enter__(self):
#         <set-up>
#            return <something> # essentially "with this state thats returned, do something"
    def __exit__(self):
#         <tear-down>
            
with Tyler() as ty:
#     <do-something-with-ty>

##### SAME THING #####
# https://docs.python-guide.org/writing/structure/
from contextlib import contextmanager
@contextmanager
def custom_open(filename):
    f = open(filename)
    try:
        yield f
    finally:
        f.close()

with custom_open('file') as f:
    contents = f.read()