Fix python_requires metadata to require >=3.6.1

[hukkin]

At least this typing.Deque import requires Python version to be >=3.6.1.

This PR fixes python_requires metadata.

[codecov]

Codecov Report

Merging #2306 (1ae018c) into master (b742c6f) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2306   +/-   ##
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  Coverage   99.97%   99.97%           
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  Files          23       23           
  Lines        4477     4477           
  Branches      903      903           
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  Hits         4476     4476           
  Misses          1        1           

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[samuelcolvin]

seems reasonable to me. Please can you:

• add a change description
• add a link in this PR to explain why Deque changed in a patch version, something strange must have happened

[hukkin]

I guess the best explanation for this is given by Guido van Rossum https://bugs.python.org/issue29011#msg283660
It's still not quite clear to me personally why the addition couldn't wait until 3.7.0 release though.

[hukkin]

• add a change description

Is there a predefined process for this? Couldn't find anything in the docs

[hukkin]

Ok I found the changelog process here. Maybe the contribution docs should link there?

[samuelcolvin]

I guess the best explanation for this is given by Guido van Rossum https://bugs.python.org/issue29011#msg283660
It's still not quite clear to me personally why the addition couldn't wait until 3.7.0 release though.

That's very weird, thanks for hunting it down.

Ok I found the changelog process here. Maybe the contribution docs should link there?

The PR template that you should have seen when creating the PR describes it pretty well, that's enough mostly.

Happy to accept a PR to update the contributing docs, otherwise I'll try to make it clearer when I get around to it.

[samuelcolvin]

Thanks a lot fo this.