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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 symmetry(self, input_entity, coefficients, duplicate=True):
 """Transforms all elementary entities symmetrically to a plane. The vector should contain four expressions giving the coefficients of the plane's equation. """

        d = {1: "Line", 2: "Surface", 3: "Volume"}
        entity = "{}{{{}}};".format(d[input_entity.dimension], input_entity.id)

        if duplicate:
            entity = "Duplicata{{{}}}".format(entity)

        self._GMSH_CODE.append(
            "Symmetry {{{}}} {{{}}}".format(
                ", ".join([str(co) for co in coefficients]), entity
            )
        )
        return