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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 match_event_roll_lengths(event_roll_a, event_roll_b, length=None):
 """Fix the length of two event rolls Parameters event_roll_a: np.ndarray, shape=(m1,k) Event roll A event_roll_b: np.ndarray, shape=(m2,k) Event roll B length: int, optional Length of the event roll, if none given, shorter event roll is padded to match longer one. Returns ------- event_roll_a: np.ndarray, shape=(max(m1,m2),k) Padded event roll A event_roll_b: np.ndarray, shape=(max(m1,m2),k) Padded event roll B """


    # Fix durations of both event_rolls to be equal
    if length is None:
        length = max(event_roll_b.shape[0], event_roll_a.shape[0])

    else:
        length = int(length)

    if length < event_roll_a.shape[0]:
        event_roll_a = event_roll_a[0:length, :]

    else:
        event_roll_a = pad_event_roll(
            event_roll=event_roll_a,
            length=length
        )

    if length < event_roll_b.shape[0]:
        event_roll_b = event_roll_b[0:length, :]

    else:
        event_roll_b = pad_event_roll(
            event_roll=event_roll_b,
            length=length
        )

    return event_roll_a, event_roll_b