code: def fit(self, struct1, struct2):
          
          struct1, struct2 = self._process_species([struct1, struct2])
  
          if not self._subset and self._comparator.get_hash(struct1.composition) \
                  != self._comparator.get_hash(struct2.composition):
              return None
  
          struct1, struct2, fu, s1_supercell = self._preprocess(struct1, struct2)
          match = self._match(struct1, struct2, fu, s1_supercell,
                              break_on_match=True)
  
          if match is None:
              return False
          else:
              return match[0] <= self.stol
docs: Fit two structures.
  
          Args:
              struct1 (Structure): 1st structure
              struct2 (Structure): 2nd structure
  
          Returns:
              True or False.