when an argument is a cell, set the local copy to NULL (see #17927)
use correct format code for exceptions
merge 3.3
remove support GCC PyArg_ParseTuple format patch, last seen in 2006
Issue #17968: Fix memory leak in os.listxattr().
Issue #17968: Fix memory leak in os.listxattr().
Complete 2 to 3 conversion
Complete 2 to 3 conversion
Silence unclosed open file ResourceWarning.
Merge with 3.3
Fix ResourceWarnings in test_sax
Fix ResourceWarnings in test_sax