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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 to_color(self):
 """Convert the grayscale image to a ColorImage. Returns ------- :obj:`ColorImage` A color image equivalent to the grayscale one. """

        color_data = np.repeat(self.data[:,:,np.newaxis], 3, axis=2)
        return ColorImage(color_data, self._frame)