code: def get_definition(self, name: YangIdentifier,
                         kw: YangIdentifier) -> Optional["Statement"]:
          
          stmt = self.superstmt
          while stmt:
              res = stmt.find1(kw, name)
              if res:
                  return res
              stmt = stmt.superstmt
          return None
docs: Search ancestor statements for a definition.
  
          Args:
              name: Name of a grouping or datatype (with no prefix).
              kw: ``grouping`` or ``typedef``.
  
          Raises:
              DefinitionNotFound: If the definition is not found.