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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(version, debug=False):
 """ Handle switching to the specified version and return None. 1. Fetch the origin. 2. Checkout the specified version. 3. Clean the repository before we begin. 4. Pull the origin when a branch; _not_ a commit id. :param version: A string containing the branch/tag/sha to be exported. :param debug: An optional bool to toggle debug output. :return: None """

    if not any(
        (_has_branch(version, debug), _has_tag(version, debug), _has_commit(
            version, debug))):
        cmd = sh.git.bake('fetch')
        util.run_command(cmd, debug=debug)
    cmd = sh.git.bake('checkout', version)
    util.run_command(cmd, debug=debug)
    cmd = sh.git.bake('clean', '-d', '-x', '-f')
    util.run_command(cmd, debug=debug)
    if _has_branch(version, debug):
        cmd = sh.git.bake('pull', rebase=True, ff_only=True)
        util.run_command(cmd, debug=debug)