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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 line(self, x1, y1, x2, y2, color="black", width=1):
 """ Draws a line between 2 points :param int x1: The x position of the starting point. :param int y1: The y position of the starting point. :param int x2: The x position of the end point. :param int y2: The y position of the end point. :param str color: The color of the line. Defaults to `"black"`. :param int width: The width of the line. Defaults to `1`. :return: The id of the line. """

        return self.tk.create_line(
            x1, y1, x2, y2, 
            width = width,
            fill = "" if color is None else utils.convert_color(color)
            )