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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 p2c(self, p=None):
 """convert from plot to canvas coordinates. See also c2p."""

        if p is None:
            p = [0, 0]
        x = (p[0] - self.x1) * self.xscale + self.cx1
        y = (p[1] - self.y1) * self.yscale + self.cy1
        # logging.debug("p2c: ({},{}) -> ({},{})".format(p[0],p[1], x, y))

        return (x, y)