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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 symmetrically_add_atom(self, specie, point, coords_are_cartesian=False):
 """ Class method for adding a site at a specified point in a slab. Will add the corresponding site on the other side of the slab to maintain equivalent surfaces. Arg: specie (str):
 The specie to add point (coords):
 The coordinate of the site in the slab to add. coords_are_cartesian (bool):
 Is the point in cartesian coordinates Returns: (Slab):
 The modified slab """


        # For now just use the species of the
        # surface atom as the element to add

        # Get the index of the corresponding site at the bottom
        point2 = self.get_symmetric_site(point, cartesian=coords_are_cartesian)

        self.append(specie, point, coords_are_cartesian=coords_are_cartesian)
        self.append(specie, point2, coords_are_cartesian=coords_are_cartesian)