The library has many constant definitions that are declared as NAME = 'val', e.g. https://github.com/aio-libs/aiohttp/blob/master/aiohttp/client.py#L161

We need to add Final type hint to let users know that these constants should be considered as immutable (this hint doesn't prevent the actual modification and fully backward compatible).

from typing_extensions import Final  # suppor

Is your feature request related to a problem? Please describe.
Related to a problem surfaced by @Shanoir on Gitter.

Describe the solution you'd like
I think that it would be a good idea for us to let users set the filename and content-type headers through the Part annotation. Maybe like so:

    @multip

Should be easy to do and good exercise. Would be cool to have some sort of social auth via github/twitter/google integration.

Some examples:
https://github.com/skftn/flask-pastebin
https://github.com/mitsuhiko/flask-pastebin

I.e. if you have a variable specified as endCursor but you wrote your query to take lastCursor, it will simply just "work" thanks to apparently GitHub just assuming null for missing variables and not caring about variables that don't line up.

Pickled pure Python MultiDicts should be unpickled as Cythonized if unpicker is executed on machine with Cython support.
And vise versa.

Will be great have approach to put some arguments for make test or commands some like this.

For that we need add some like that into Makefile.

# arguments
FIRST_ARG := $(firstword $(MAKECMDGOALS))
ARGS = $(filter-out $@,$(MAKEOVERRIDES) $(MAKECMDGOALS))
MAKEFILE_PATH := $(abspath $(firstword $(MAKEFILE_LIST)))

%:
	@:

and after that add ${ARGS} to our commands

te