Add a small number of type hints

[willfurnass]

Demonstrates what could be done to address Issue #328

[codecov-io]

Codecov Report

Merging #334 into master will increase coverage by <.01%.
The diff coverage is 100%.

@@            Coverage Diff            @@
##           master    #334      +/-   ##
=========================================
+ Coverage   70.79%   70.8%   +<.01%     
=========================================
  Files           2       2              
  Lines        5465    5466       +1     
  Branches     1501    1501              
=========================================
+ Hits         3869    3870       +1     
  Misses       1212    1212              
  Partials      384     384

Impacted Files	Coverage Δ
mumot/__init__.py	70.79% <100%> (ø)	⬆️

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