def _match_vcs_scheme(url):<EOL>
from pipenv.patched.notpip._internal.vcs import VcsSupport<EOL>for scheme in VcsSupport.schemes:<EOL><INDENT>if url.lower().startswith(scheme) and url[len(scheme)] in '<STR_LIT>':<EOL><INDENT>return scheme<EOL><DEDENT><DEDENT>return None<EOL>
Look for VCS schemes in the URL.

    Returns the matched VCS scheme, or None if there's no match.