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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 repeat_str(state):
 """Convert internal API repeat state to string."""

    if state == const.REPEAT_STATE_OFF:
        return 'Off'
    if state == const.REPEAT_STATE_TRACK:
        return 'Track'
    if state == const.REPEAT_STATE_ALL:
        return 'All'
    return 'Unsupported'