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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 pad_event_roll(event_roll, length):
 """Pad event roll's length to given length Parameters event_roll: np.ndarray, shape=(m,k) Event roll length : int Length to be padded Returns ------- event_roll: np.ndarray, shape=(m,k) Padded event roll """


    if length > event_roll.shape[0]:
        padding = numpy.zeros((length-event_roll.shape[0], event_roll.shape[1]))
        event_roll = numpy.vstack((event_roll, padding))

    return event_roll