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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 save(filepath, obj, compressed=True):
 """ Save the object to a .npz file. Parameters filepath : str The path to save the file. obj: `pypianoroll.Multitrack` objects The object to be saved. """

    if not isinstance(obj, Multitrack):
        raise TypeError("Support only `pypianoroll.Multitrack` class objects")
    obj.save(filepath, compressed)