Remove Python 2 support

[Seanny123]

Although explicitly unsupported, there was still some code hanging around for Python 2, which is removed in this PR.

[codecov]

Codecov Report

Merging #25 into fork will increase coverage by 5.76%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##             fork       #25      +/-   ##
===========================================
+ Coverage   94.23%   100.00%   +5.76%     
===========================================
  Files           1         1              
  Lines         104        95       -9     
===========================================
- Hits           98        95       -3     
+ Misses          6         0       -6     

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[althonos]

Good catch, thanks. I will post a new release ASAP.

[Seanny123]

@althonos did you know Python has built-in support for cached_property? Does this built-in support make parts of this project obsolete?

[althonos]

@Seanny123 : the Python cached_property comes from the cached-property library, which this repo is a fork of, fixing a lot of bugs back from the Python 3.6 era. The builtin version has been incorporated as it, which means it still has the quirks of the original version. Most notably, functools.cached_property does not derive from property, which has some unfortunate side effect with some libraries.

Check out the original (and very much ignored) pull request here: pydanny#137