Allow to pass functions to PythonNode(hash=...).

[tobiasraabe]

Changes

Provide a description and/or bullet points to describe the changes in this PR.

Todo

• Reference issues which can be closed due to this PR with "Closes #x".
• Review whether the documentation needs to be updated.
• Document PR in docs/changes.rst.

[codecov]

Codecov Report

Merging #410 (b2ba9c1) into main (453faf0) will increase coverage by 0.01%.
The diff coverage is 100.00%.

❗ Current head b2ba9c1 differs from pull request most recent head 647d412. Consider uploading reports for the commit 647d412 to get more accurate results

@@            Coverage Diff             @@
##             main     #410      +/-   ##
==========================================
+ Coverage   95.64%   95.66%   +0.01%     
==========================================
  Files          94       94              
  Lines        8294     8303       +9     
==========================================
+ Hits         7933     7943      +10     
+ Misses        361      360       -1     

Flag	Coverage Δ
end_to_end	82.93% <60.00%> (-0.03%)	⬇️
integration	39.55% <50.00%> (+<0.01%)	⬆️
unit	66.06% <100.00%> (+0.09%)	⬆️

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Files Changed	Coverage Δ
src/_pytask/nodes.py	94.06% <100.00%> (+0.96%)	⬆️
tests/test_nodes.py	100.00% <100.00%> (ø)