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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 _updateImage(self):

 """Internal method to render text as an image."""

        # Fill the background of the image
        if self.backgroundColor is not None:
            self.textImage.fill(self.backgroundColor)

        # Render the text as a single line, and blit it onto the textImage surface
        if self.mask is None:
            lineSurface = self.font.render(self.text, True, self.textColor)
        else:
            nChars = len(self.text)
            maskedText = self.mask * nChars
            lineSurface = self.font.render(maskedText, True, self.textColor)
        self.textImage.blit(lineSurface, (0, 0))