code: def get_mass(self):
          '''Returns mass'''
          mass = parsers.get_mass(self.__chebi_id)
  
          if math.isnan(mass):
              mass = parsers.get_mass(self.get_parent_id())
  
          if math.isnan(mass):
              for parent_or_child_id in self.__get_all_ids():
                  mass = parsers.get_mass(parent_or_child_id)
  
                  if not math.isnan(mass):
                      break
  
          return masf get_mass(self):
          '''Returns mass'''
          mass = parsers.get_mass(self.__chebi_id)
  
          if math.isnan(mass):
              mass = parsers.get_mass(self.get_parent_id())
  
          if math.isnan(mass):
              for parent_or_child_id in self.__get_all_ids():
                  mass = parsers.get_mass(parent_or_child_id)
  
                  if not math.isnan(mass):
                      break
  
          return mass
docs: Returns mass