Flask compatibility with python 3.7

[sdreyer]

Description

Type of change

Does this correspond to an open issue?

Select type(s) of change

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update

Checklist:

• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• I have fixed any merge conflicts

[codecov]

Codecov Report

Merging #1111 (46bf06d) into main (3bebf40) will decrease coverage by 0.08%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main    #1111      +/-   ##
==========================================
- Coverage   39.34%   39.26%   -0.08%     
==========================================
  Files         114      115       +1     
  Lines       21399    21784     +385     
==========================================
+ Hits         8419     8554     +135     
- Misses      12507    12746     +239     
- Partials      473      484      +11     

see 21 files with indirect coverage changes

📣 We’re building smart automated test selection to slash your CI/CD build times. Learn more