Breaks with Python 3.6

[grofte]

Checklist

• [not applicable] The bug is reproducible against the latest release and/or master.
• There are no similar issues or pull requests to fix it yet.

Describe the bug

I used uvicorn==0.11.8 because it worked with my build (Tensorflow, CUDA and a bunch of other stuff). It worked and uses Python 3.6.x (I don't remember the exact version). For PyPi you folks have specified click==7.* which is terrible. But the breaking part is uvloop>=0.14.0 because uvloop 0.15 requires Python 3.7+

    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-7glbpqte/uvloop/setup.py", line 5, in <module>
        raise RuntimeError('uvloop requires Python 3.7 or greater')
    RuntimeError: uvloop requires Python 3.7 or greater

To reproduce

make a dockerfile like

FROM tensorflow/tensorflow:2.4.0-gpu-jupyter
RUN pip install uvicorn==0.11.8

run

docker build .

Expected behavior

That when I install a specific version of uvicorn then I get that specific version.

Actual behavior

When I install a specific version of uvicorn I get that version but semi-arbitrary versions of uvicorn's dependencies.

Debugging material

 Collecting uvicorn==0.11.8
  Downloading uvicorn-0.11.8-py3-none-any.whl (43 kB)
Collecting click==7.*
  Downloading click-7.1.2-py2.py3-none-any.whl (82 kB)
Collecting h11<0.10,>=0.8
  Downloading h11-0.9.0-py2.py3-none-any.whl (53 kB)
Collecting uvloop>=0.14.0; sys_platform != "win32" and sys_platform != "cygwin" and platform_python_implementation != "PyPy"
  Downloading uvloop-0.15.0.tar.gz (2.1 MB)
    ERROR: Command errored out with exit status 1:
     command: /usr/bin/python3 -c 'import sys, setuptools, tokenize; sys.argv[0] = '"'"'/tmp/pip-install-7glbpqte/uvloop/setup.py'"'"'; __file__='"'"'/tmp/pip-install-7glbpqte/uvloop/setup.py'"'"';f=getattr(tokenize, '"'"'open'"'"', open)(__file__);code=f.read().replace('"'"'\r\n'"'"', '"'"'\n'"'"');f.close();exec(compile(code, __file__, '"'"'exec'"'"'))' egg_info --egg-base /tmp/pip-pip-egg-info-2wkiop5k
         cwd: /tmp/pip-install-7glbpqte/uvloop/
    Complete output (5 lines):
    Traceback (most recent call last):
      File "<string>", line 1, in <module>
      File "/tmp/pip-install-7glbpqte/uvloop/setup.py", line 5, in <module>
        raise RuntimeError('uvloop requires Python 3.7 or greater')
    RuntimeError: uvloop requires Python 3.7 or greater
    ----------------------------------------
ERROR: Command errored out with exit status 1: python setup.py egg_info Check the logs for full command output.

Environment

• OS / Python / Uvicorn version: Ubuntu

PS yes, I'll fix this myself. I am working towards an automated pipeline and this makes it fairly obvious that I should create an intermediate docker image to create new service images from (rather than download every time) for greater resilience but I just can't imagine why you would set things up this way. Your readme even says Python 3.6+ at the very top.

[euri10]

your agressive tone just put your issue at the very bottom of my todo list

[graingert]

@grofte looks like it was fixed here #952