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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 validate_coordinates(self, x, y):
 """ Check if the piece lie within the board. """

        if not(0 <= x < self.length and 0 <= y < self.height):
            raise ForbiddenCoordinates(
                "x={}, y={} outside of {}x{} board.".format(
                    x, y, self.length, self.height))