在types模块里了
types.FunctionType
types.LambdaType
The type of user-defined functions and functions created by lambda expressions.
types.MethodType
The type of methods of user-defined class instances.
types.BuiltinFunctionType
types.BuiltinMethodType
The type of built-in functions like len() or sys.exit(), and methods of built-in classes. (Here, the term “built-in” means “written in C”.)