In Debian, we run tests with PYTHONWARNINGS=default environment variable exported. With this configuration, the test_deprecation_warning test in InputTests class fails:
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FAIL: test_deprecation_warning (test_io.InputTests)
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Traceback (most recent call last):
File "/builds/python-team/modules/python-docutils/debian/output/python-docutils-0.15+dfsg/test3/test_io.py", line 149, in test_deprecation_warning
list(v.category for v in w))
AssertionError: 1 != 0 : Expected no warnings, got [<class 'ResourceWarning'>]
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The attached patch fixes this failure.
