Add support for type checking with upcomming Numpy 1.20 release.

[jenshnielsen]

Checked locally with numpy 1.20 rc1

• Some numpy types are now generic so give them an explicit Any. Use types in strings to support older numpy versions
• np.int, np.float and np.complex which are aliases for the build in python types are deprecated.
• Use the dtype constructor explicitly when needed
• Various fixes for interaction between the python types and numpy types

EDIT:
while this does run with older versions of numpy it does not type check. Not sure what the best solution is.
We can add ignores to those lines or just wait until numpy 1.20 is officially released. Or we could disable the non explicit generics for now.

[astafan8]

while this does run with older versions of numpy it does not type check

you mean that it doesn't typecheck with "old verions of numpy" (and the current version of stubs)? then it sounds like the best thing to do is to wait for 1.20 to be released, merge this PR immediately then, and never worry about 1.19 and before ever again.

[jenshnielsen]

@astafan8 I realized that we can just get this passing with older numpy versions by removing the stubs. I think this is ready for review but I would like to merge #2569 first so we ensure that this does not break any older numpy versions

[codecov]

Codecov Report

Merging #2499 (e8d3fa1) into master (52d7e69) will decrease coverage by 0.01%.
The diff coverage is 66.66%.

@@            Coverage Diff             @@
##           master    #2499      +/-   ##
==========================================
- Coverage   63.62%   63.60%   -0.02%     
==========================================
  Files         198      198              
  Lines       25913    25929      +16     
==========================================
+ Hits        16486    16493       +7     
- Misses       9427     9436       +9     

[astafan8]

@jenshnielsen ok, good! is it worth waiting until the stubs start matching the types of numpy 1.20? or is the issue somewhere else? I guess since the stubs are not an official released project (right?), we'd better just stick to numpy 1.20 since it's the latest nunmpy that will alweays be installed when we run mypy in CI?

[jenshnielsen]

@astafan8 The stubs are deprecated and will never be updated. The types in numpy 1.20 are the official source of truth