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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_to_same(obj):
 """ Return a copy of the object with shorter piano-rolls padded with zeros at the end along the time axis to the length of the piano-roll with the maximal length. """

    if not isinstance(obj, Multitrack):
        raise TypeError("Support only `pypianoroll.Multitrack` class objects")
    copied = deepcopy(obj)
    copied.pad_to_same()
    return copied