Support Python 3.9

[jodal]

No description provided.

[codecov]

Codecov Report

Merging #33 (9d16f53) into master (60e779b) will increase coverage by 0.44%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #33      +/-   ##
==========================================
+ Coverage   90.80%   91.25%   +0.44%     
==========================================
  Files           6        6              
  Lines         446      446              
==========================================
+ Hits          405      407       +2     
+ Misses         41       39       -2     

Impacted Files	Coverage Δ
mopidy_mpris/player.py	97.70% <0.00%> (+0.76%)	⬆️

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