docs: def validate_mutations(self, mutations):
          '''This function has been refactored to use the SimpleMutation class.
             The parameter is a list of Mutation objects. The function has no return value but raises a PDBValidationException
             if the wildtype in the Mutation m does not match the residue type corresponding to residue m.ResidueID in the PDB file.
          '''
          # Chain, ResidueID, WildTypeAA, MutantAA
          resID2AA = self.get_residue_id_to_type_map()
          badmutations = []
          for m in mutations:
              wildtype = resID2AA.get(PDB.ChainResidueID2String(m.Chain, m.ResidueID), "")
              if m.WildTypeAA != wildtype:
                  badmutations.append(m)
          if badmutations:
              raise PDBValidationException("The mutation(s) %s could not be matched against the PDB %s." % (", ".join(map(str, badmutations)), self.pdb_id))