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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 _get_version_from_git_tag(path):
 """Return a PEP440-compliant version derived from the git status. If that fails for any reason, return the changeset hash. """

    m = GIT_DESCRIBE_REGEX.match(_git_describe_tags(path) or '')
    if m is None:
        return None
    version, post_commit, hash = m.groups()
    return version if post_commit == '0' else "{0}.post{1}+{2}".format(version, post_commit, hash)