Fix tests for #11798
Tighten-up the lookkey() logic and beautify the code a bit.

Use less code by moving many of the steps from the initial
lookup into the main search loop.

Beautify the code but keep the overall logic unchanged.
Issue #18760: Improved cross-references in the xml package.
Issue #18760: Improved cross-references in the xml package.
Issue #18743: Fix references to non-existant "StringIO" module
in docstrings and comments.
Issue #18743: Fix references to non-existant "StringIO" module
in docstrings and comments.
Issue #16799: Switched from getopt to argparse style in regrtest's argument
parsing.  Added more tests for regrtest's argument parsing.
Issue #17974: Switch unittest from using getopt to using argparse.
Issue #8713: Test should not print message about start method.
Issue #8713: Cleanup before saving process._dangling.
Issue #8713: Print dangling processes/threads, if any.
Issue #18643: Fix some test_socket failures due to large default socket buffer
sizes.
Issue #18643: Fix some test_socket failures due to large default socket buffer
sizes.
Merge.
Merge.
Null merge of 3.3 into default.
Fixes issue #15507: test_subprocess's test_send_signal could fail if the test
runner were run in an environment where the process inherited an ignore
setting for SIGINT.  Restore the SIGINT handler to the desired
KeyboardInterrupt raising one during that test.
Fixes Issue #15507: test_subprocess's test_send_signal could fail if the test
runner were run in an environment where the process inherited an ignore
setting for SIGINT.  Restore the SIGINT handler to the desired
KeyboardInterrupt raising one during that test.
make lists uniformly integers for the benefit of pypy
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