code: def get_default(self, stmt, refd):
          
          if refd["default"]:
                  return refd["default"]
          defst = stmt.search_one("default")
          if defst:
              return defst.arg
          return None
docs: Return default value for `stmt` node.
  
          `refd` is a dictionary of applicable refinements that is
          constructed in the `process_patches` method.