Checks to see if the PDB file has been deprecated and, if so, what the new ID is.

def parse_deprecated_tags(self, name, attributes):
        '''Checks to see if the PDB file has been deprecated and, if so, what the new ID is.'''
        if name == 'PDBx:pdbx_database_PDB_obs_spr':
            self.counters['PDBx:pdbx_database_PDB_obs_spr'] = self.counters.get('PDBx:pdbx_database_PDB_obs_spr', 0) + 1
            old_pdb_id = attributes.get('replace_pdb_id').upper()
            new_pdb_id = attributes.get('pdb_id').upper()
            assert(old_pdb_id and new_pdb_id)

            if self.pdb_id == old_pdb_id:
                self.deprecated = True
                self.replacement_pdb_id = new_pdb_id
            else:
                assert(self.pdb_id == new_pdb_id)