Source code: Lib/types.py
This module defines names for some object types that are used by the standard Python interpreter, but not exposed as builtins like int or str are. Also, it does not include some of the types that arise transparently during processing such as the listiterator type.
Typical use is for isinstance() or issubclass() checks.
The module defines the following names:
The type of user-defined functions and functions created by lambda expressions.
The type of generator-iterator objects, produced by calling a generator function.
The type of methods of user-defined class instances.
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”.)
The type of modules.
The type of traceback objects such as found in sys.exc_info()[2].
The type of frame objects such as found in tb.tb_frame if tb is a traceback object.
The type of objects defined in extension modules with PyGetSetDef, such as FrameType.f_locals or array.array.typecode. This type is used as descriptor for object attributes; it has the same purpose as the property type, but for classes defined in extension modules.
The type of objects defined in extension modules with PyMemberDef, such as datetime.timedelta.days. This type is used as descriptor for simple C data members which use standard conversion functions; it has the same purpose as the property type, but for classes defined in extension modules.
CPython implementation detail: In other implementations of Python, this type may be identical to GetSetDescriptorType.