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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 x_tic_points(self, interval):
        "Return the list of X values for which tick marks and grid lines are drawn."
        if type(interval) == FunctionType:
            return interval(*self.x_range)

        return self.x_coord.get_tics(self.x_range[0], self.x_range[1], interval)