code: def generic_visit(self, node, iter_fields=ast.iter_fields, AST=ast.AST):
          
          for field, value in iter_fields(node):
              if isinstance(value, list):
                  for item in value:
                      if isinstance(item, AST):
                          self.visit(item)
              elif isinstance(value, AST):
                  self.visit(value)
docs: Called if no explicit visitor function exists for a node.