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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 commit_branches(sha1):
 # type: (str) -> List[str] """ Get the name of the branches that this commit belongs to. """

    cmd = 'git branch --contains {}'.format(sha1)
    return shell.run(
        cmd,
        capture=True,
        never_pretend=True
    ).stdout.strip().split()