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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 cube2map(data_cube, layout):
 r"""Cube to Map This method transforms the input data from a 3D cube to a 2D map with a specified layout Parameters data_cube : np.ndarray Input data cube, 3D array of 2D images Layout : tuple 2D layout of 2D images Returns ------- np.ndarray 2D map Raises ------ ValueError For invalid data dimensions ValueError For invalid layout Examples -------- array([[ 0, 1, 4, 5], [ 2, 3, 6, 7], [ 8, 9, 12, 13], [10, 11, 14, 15]]) """


    if data_cube.ndim != 3:
        raise ValueError('The input data must have 3 dimensions.')

    if data_cube.shape[0] != np.prod(layout):
        raise ValueError('The desired layout must match the number of input '
                         'data layers.')

    return np.vstack([np.hstack(data_cube[slice(layout[1] * i, layout[1] *
                      (i + 1))]) for i in range(layout[0])])