Support for Python 3.9

[allentv]

Python 3.9 is out. I would like to add support for this version.

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[hiranya911]

It should already work on Python 3.9 even if it's not documented. Did you have any problems installing on Python 3.9?

[allentv]

Nothing yet. Just wanted to make sure the version is mentioned in the docs

[hiranya911]

Our docs already indicate our Python requirement as 3.5+ (3.6+ recommended). Updating CI and package metadata is nice, but I don't think it's too urgent. We will get to it in the coming weeks.

[brauli0]

• OS: macOS Big Sur Version 11.1
• Python version: 3.9.0
• pip version: 20.2.3

Hi! I'm new here, sorry if I'm misunderstanding something or I should open a new issue but I can't install firebase-admin with pip:

$ pip install firebase-admin
...
Requirement already satisfied: pyasn1<0.5.0,>=0.4.6 in ./env/lib/python3.9/site-packages (from pyasn1-modules>=0.2.1->google-auth>=1.16.0->google-api-python-client>=1.7.8->firebase-admin) (0.4.8)
Using legacy 'setup.py install' for grpcio, since package 'wheel' is not installed.
Using legacy 'setup.py install' for msgpack, since package 'wheel' is not installed.
Installing collected packages: httplib2, google-auth-httplib2, uritemplate, grpcio, google-api-core, google-api-python-client, google-cloud-core, google-cloud-firestore, msgpack, cachecontrol, google-crc32c, google-resumable-media, google-cloud-storage, firebase-admin
    Running setup.py install for grpcio ... error
    ERROR: Command errored out with exit status 1:
     command: [...]/env/bin/python3 -u -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/private/var/folders/57/d13y13tx3t93sf7fklthcsch0000gn/T/pip-install-vl1_ural/grpcio/setup.py'"'"'; __file__='"'"'/private/var/folders/57/d13y13tx3t93sf7fklthcsch0000gn/T/pip-install-vl1_ural/grpcio/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' install --record /private/var/folders/57/d13y13tx3t93sf7fklthcsch0000gn/T/pip-record-ymesbbyo/install-record.txt --single-version-externally-managed --compile --install-headers [...]/env/include/site/python3.9/grpcio
         cwd: /private/var/folders/57/d13y13tx3t93sf7fklthcsch0000gn/T/pip-install-vl1_ural/grpcio/
    Complete output (1900 lines):

There is a problem with grpcio. I'd like to know if there is a way to make it work without downgrading python as suggested in some forums. Thanks.

[brauli0]

I've just solve the problem upgrading pip to version 21.0