asyncio.Task.current_task PendingDeprecation fix

[Amertz08]

Issue #, if available:

Resolves #216

Description of changes:

Change asyncio.Task.current_task invocation to asyncio.current_task to alleviate PendingDeprecationWarning

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[Amertz08]

Yeah so unfortunately simply changing the invocation won't work with 3.5 and 3.6. I think the 2 solutions would be to either do a try/except catch of an AttributeError and then fall back to the compatible version or use and if/else off of sys.version_info. The latter would be more clean imo.

[bhautikpip]

Yes. I also think use of sys.version_info would be more cleaner.

[codecov-io]

Codecov Report

Merging #217 into master will increase coverage by 0.04%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #217      +/-   ##
==========================================
+ Coverage   84.48%   84.53%   +0.04%     
==========================================
  Files          80       80              
  Lines        3120     3130      +10     
==========================================
+ Hits         2636     2646      +10     
  Misses        484      484              

Impacted Files	Coverage Δ
aws_xray_sdk/core/async_context.py	91.52% <100.00%> (+1.72%)	⬆️

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[Amertz08]

Looks like it is all back to green in the test suite. Not sure why the check isn't working.

[bhautikpip]

I would also add condition which checks sys.version_info.major is 2 and 3 because in the case of major version 4.0 above condition would break.

[Amertz08]

Do we need a guard against 4? I think we do need to make sure its python3. I forgot python 2.7 had asyncio support. So I assumed no python2 code would call this code and if it did it would error for other reasons.

So basically just this.

_GTE_PY37 = sys.version_info.major == 3 and  sys.version_info.minor >= 7

[bhautikpip]

Yep. I think this makes sense.

[bhautikpip]

Looks good :)