numpy.ndarray.__array__
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ndarray.__array__(|dtype) → reference if type unchanged, copy otherwise.
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Returns either a new reference to self if dtype is not given or a new array of provided data type if dtype is different from the current dtype of the array. 
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Licensed under the NumPy License.
    https://docs.scipy.org/doc/numpy-1.11.0/reference/generated/numpy.ndarray.__array__.html