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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 astype(self, dtype, copy=True):
 """ Cast to a NumPy array with 'dtype'. Parameters dtype : str or dtype Typecode or data-type to which the array is cast. copy : bool, default True Whether to copy the data, even if not necessary. If False, a copy is made only if the old dtype does not match the new dtype. Returns ------- array : ndarray NumPy ndarray with 'dtype' for its dtype. """

        return np.array(self, dtype=dtype, copy=copy)