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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 _visit_te_shape(self, shape: ShExJ.shapeExpr, visit_center: _VisitorCenter) -> None: """ Visit a shape expression that was reached through a triple expression. This, in turn, is used to visit additional triple expressions that are referenced by the Shape :param shape: Shape reached through triple expression traverse :param visit_center: context used in shape visitor """

        if isinstance(shape, ShExJ.Shape) and shape.expression is not None:
            visit_center.f(visit_center.arg_cntxt, shape.expression, self)