python/samba: Add cmp_fn and cmp_to_key_fn functions for py2/py3
the cmp function and the cmp paramater (e.g. to sort functions)
no longer exist in python3.
cmp_fn is provides the missing functionality of the py2 cmp builtin
function.
cmp_to_key_fn allows the key paramater (e.g. for sort) to use the
old py2 cmp function for sorting. Note: the cmp_to_key is present in
since 2.7 (hence the inclusion of the source code for this function pre
that version)
Signed-off-by: Noel Power <noel.power@suse.com>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>
Reviewed-by: Andreas Schneider <asn@samba.org>
Signed-off-by: Joe Guo <joeg@catalyst.net.nz>