tests/sha256line.py

cext: fix potential memory leaks of list items appended with PyList_Append

Also reduce the duplication in the tricky code that uses PyList_Append by
extracting it into a function `pylist_append_owned`.

#!/usr/bin/env python3
#
# A tool to help producing large and poorly compressible files
#
# Usage:
#   $TESTDIR/seq.py 1000 | $TESTDIR/sha256line.py > my-file.txt


import hashlib
import sys


for line in sys.stdin:
    print(hashlib.sha256(line.encode('utf8')).hexdigest())