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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_remove_atoms(self, indices):
 """ Class method for removing sites corresponding to a list of indices. Will remove the corresponding site on the other side of the slab to maintain equivalent surfaces. Arg: indices ([indices]):
 The indices of the sites in the slab to remove. """


        slabcopy = SpacegroupAnalyzer(self.copy()).get_symmetrized_structure()
        points = [slabcopy[i].frac_coords for i in indices]
        removal_list = []
        
        for pt in points:
            # Get the index of the original site on top
            cart_point = slabcopy.lattice.get_cartesian_coords(pt)
            dist = [site.distance_from_point(cart_point) for site in slabcopy]
            site1 = dist.index(min(dist))

            # Get the index of the corresponding site at the bottom
            for i, eq_sites in enumerate(slabcopy.equivalent_sites):
                if slabcopy[site1] in eq_sites:
                    eq_indices = slabcopy.equivalent_indices[i]
                    break
            i1 = eq_indices[eq_sites.index(slabcopy[site1])]
            
            for i2 in eq_indices:
                if i2 == i1:
                    continue
                if slabcopy[i2].frac_coords[2] == slabcopy[i1].frac_coords[2]:
                    continue
                # Test site remove to see if it results in symmetric slab
                s = self.copy()
                s.remove_sites([i1, i2])
                if s.is_symmetric():
                    removal_list.extend([i1, i2])
                    break
                    
        # If expected, 2 atoms are removed per index
        if len(removal_list) == 2*len(indices):
            self.remove_sites(removal_list)
        else:
            warnings.warn("Equivalent sites could not be found for removal for all indices. Surface unchanged.")