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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 set_pixels(self, pixels):
 """ Set the image data. Will not work if the new image has a different shape than the current image. Parameters pixels : numpy.ndarray New image data Returns ------- None """

        if not (pixels.shape == self._pixels.shape):
            raise AssertionError("Shape mismatch between pixels supplied {0} and existing image pixels {1}".format(pixels.shape,self._pixels.shape))
        self._pixels = pixels
        # reset this so that it is calculated next time the function is called
        self._rms = None
        return