def parseSourceURL(source_url):
name, spec = _getNonRegistryRef(source_url)<EOL>if spec:<EOL><INDENT>return spec<EOL><DEDENT>try:<EOL><INDENT>url_is_spec = version.Spec(source_url)<EOL><DEDENT>except ValueError:<EOL><INDENT>url_is_spec = None<EOL><DEDENT>if url_is_spec is not None:<EOL><INDENT>return VersionSource('<STR_LIT>', '<STR_LIT>', source_url)<EOL><DEDENT>raise InvalidVersionSpec("<STR_LIT>" % (source_url))<EOL>
Parse the specified version source URL (or version spec), and return an
        instance of VersionSource