## 5.2.2 Which Docstrings Are Examined?

See the docstrings in doctest.py for all the details. They're unsurprising: the module docstring, and all function, class and method docstrings are searched. Optionally, the tester can be directed to exclude docstrings attached to objects with private names. Objects imported into the module are not searched.

In addition, if `M.__test__` exists and "is true", it must be a dict, and each entry maps a (string) name to a function object, class object, or string. Function and class object docstrings found from `M.__test__` are searched even if the the tester has been directed to skip over private names in the rest of the module. In output, a key `K` in `M.__test__` appears with name

    <name of M>.__test__.K

Any classes found are recursively searched similarly, to test docstrings in their contained methods and nested classes. While private names reached from `M`'s globals can be optionally skipped, all names reached from `M.__test__` are searched.