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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 numpy_array_from_list_or_numpy_array(vectors):
 """ Returns numpy array representation of argument. Argument maybe numpy array (input is returned) or a list of numpy vectors. """

    # If vectors is not a numpy matrix, create one
    if not isinstance(vectors, numpy.ndarray):
        V = numpy.zeros((vectors[0].shape[0], len(vectors)))
        for index in range(len(vectors)):
            vector = vectors[index]
            V[:, index] = vector
        return V

    return vectors