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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 _radial_distance(shape):
 """ Return an array where each value is the Euclidean distance from the array center. Parameters shape : tuple of int The size of the output array along each axis. Returns ------- result : `~numpy.ndarray` An array containing the Euclidian radial distances from the array center. """


    if len(shape) != 2:
        raise ValueError('shape must have only 2 elements')
    position = (np.asarray(shape) - 1) / 2.
    x = np.arange(shape[1]) - position[1]
    y = np.arange(shape[0]) - position[0]
    xx, yy = np.meshgrid(x, y)
    return np.sqrt(xx**2 + yy**2)