def METHOD_NAME():
    def f1():
        """
        docstring headline
        other text
        """
    def f2():
        """
        docstring
        headline
        other text
        """
    def f3():
        pass
    assert util.docstring_headline(f1) == 'docstring headline'
    assert util.docstring_headline(f2) == 'docstring headline'
    assert util.docstring_headline(f3) == ''