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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 rfft2(a, s=None, axes=(-2, -1), norm=None):
 """ Compute the 2-dimensional FFT of a real array. Parameters a : array Input array, taken to be real. s : sequence of ints, optional Shape of the FFT. axes : sequence of ints, optional Axes over which to compute the FFT. norm : {None, "ortho"}, optional .. versionadded:: 1.10.0 Normalization mode (see `numpy.fft`). Default is None. Returns ------- out : ndarray The result of the real 2-D FFT. See Also -------- rfftn : Compute the N-dimensional discrete Fourier Transform for real input. Notes ----- This is really just `rfftn` with different default behavior. For more details see `rfftn`. """


    return rfftn(a, s, axes, norm)