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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _match_vcs_scheme(url):
 # type: (str) -> Optional[str] """Look for VCS schemes in the URL. Returns the matched VCS scheme, or None if there's no match. """

    from pipenv.patched.notpip._internal.vcs import VcsSupport
    for scheme in VcsSupport.schemes:
        if url.lower().startswith(scheme) and url[len(scheme)] in '+:':
            return scheme
    return None