Python 3.10 AttributeError: module 'collections' has no attribute 'Iterable'

[jeffbr13]

Hi there! Just thought I'd let you know that the deprecated abstract base classes aliases were removed in Python 3.10 (change) and this is causing an AttributeError wherever collections.Iterable etc. are used.

======================================================== ERRORS ========================================================
__________________________________ ERROR collecting tests/test_import_csv_to_graph.py __________________________________
tests/test_import_csv_to_graph.py:8: in <module>
    from hypothesis_csv.strategies import csv as csv_strategy
../../../../Library/Caches/pypoetry/virtualenvs/my-app-HgQtD8X_-py3.10/lib/python3.10/site-packages/hypothesis_csv/strategies.py:1: in <module>
    from hypothesis_csv import _csv
../../../../Library/Caches/pypoetry/virtualenvs/my-app-HgQtD8X_-py3.10/lib/python3.10/site-packages/hypothesis_csv/_csv.py:6: in <module>
    from hypothesis_csv._data_rows import *
../../../../Library/Caches/pypoetry/virtualenvs/my-app-HgQtD8X_-py3.10/lib/python3.10/site-packages/hypothesis_csv/_data_rows.py:21: in <module>
    def get_columns(draw, columns: isa(collections.Iterable)):
E   AttributeError: module 'collections' has no attribute 'Iterable'
=============================================== short test summary info ================================================
ERROR tests/test_import_csv_to_graph.py - AttributeError: module 'collections' has no attribute 'Iterable'

The fix is to replace collections.Iterable and similar lookups with collections.abc.….

[jeffbr13]

I've provided PR #4 which fixes this issue.