def parse_reference(reference):
if "<STR_LIT::>" in reference:<EOL><INDENT>im, tag = reference.rsplit("<STR_LIT::>", <NUM_LIT:1>)<EOL>if "<STR_LIT:/>" in tag:<EOL><INDENT>return (reference, "<STR_LIT>")<EOL><DEDENT>else:<EOL><INDENT>return (im, tag)<EOL><DEDENT><DEDENT>else:<EOL><INDENT>return (reference, "<STR_LIT>")<EOL><DEDENT>
parse provided image reference into <image_repository>:<tag>

:param reference: str, e.g. (registry.fedoraproject.org/fedora:27)
:return: collection (tuple or list), ("registry.fedoraproject.org/fedora", "27")