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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 _clear(self):
 """ Clear the current image. """

        self._plain_image = [" " * self._width for _ in range(self._height)]
        self._colour_map = [[(None, 0, 0) for _ in range(self._width)]
                            for _ in range(self._height)]