code: def implicify_hydrogens(self):
          
          total = 0
          for ml in (self.__reagents, self.__reactants, self.__products):
              for m in ml:
                  if hasattr(m, 'implicify_hydrogens'):
                      total += m.implicify_hydrogens()
          if total:
              self.flush_cache()
          return total
docs: remove explicit hydrogens if possible
  
          :return: number of removed hydrogens