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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 _has_commit(version, debug=False):
 """ Determine a version is a local git commit sha or not. :param version: A string containing the branch/tag/sha to be determined. :param debug: An optional bool to toggle debug output. :return: bool """

    if _has_tag(version, debug) or _has_branch(version, debug):
        return False
    cmd = sh.git.bake('cat-file', '-e', version)
    try:
        util.run_command(cmd, debug=debug)
        return True
    except sh.ErrorReturnCode:
        return False