code: def typedef(
              self,
              name=None,
              function=None,
              header_dir=None,
              header_file=None,
              recursive=None):
          
          return (
              self._find_single(
                  self._impl_matchers[scopedef_t.typedef],
                  name=name,
                  function=function,
                  decl_type=self._impl_decl_types[
                      scopedef_t.typedef],
                  header_dir=header_dir,
                  header_file=header_file,
                  recursive=recursive)
          )
docs: returns reference to typedef declaration, that is matched
          defined criteria