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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 read_frame(self):
 """Reads a frame and converts the color if needed. In case no frame is available, i.e. self.capture.read() returns False as the first return value, the event_source of the TimedAnimation is stopped, and if possible the capture source released. Returns: None if stopped, otherwise the color converted source image. """

        ret, frame = self.capture.read()
        if not ret:
            self.event_source.stop()
            try:
                self.capture.release()
            except AttributeError:
                # has no release method, thus just pass
                pass
            return None
        if self.convert_color != -1 and is_color_image(frame):
            return cv2.cvtColor(frame, self.convert_color)
        return frame