class foo:
    @staticmethod
    def bar():
        """Non working doctest
        >>> GLOBAL = 'global'
        >>> foo.bar()
        Traceback (most recent call last):
            ...
        NameError: name 'GLOBAL' is not defined
        >>> foo.bar.__globals__['GLOBAL'] = GLOBAL
        >>> foo.bar()
        global
        """
        print(GLOBAL)
import doctest
doctest.testmod()