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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 branches():
 # type: () -> List[str] """ Return a list of branches in the current repo. Returns: list[str]: A list of branches in the current repo. """

    out = shell.run(
        'git branch',
        capture=True,
        never_pretend=True
    ).stdout.strip()
    return [x.strip('* \t\n') for x in out.splitlines()]