How to use the justext.utils.normalize_whitespace function in jusText

def test_normalize_newline_and_tab(self):
        string = "123 \n456\t\n"
        expected = "123\n456\n"
        assert expected == normalize_whitespace(string)

def test_normalize_no_change(self):
        string = "a b c d e f g h i j k l m n o p q r s ..."
        assert string == normalize_whitespace(string)

def test_normalize_dont_trim(self):
        string = "  a b c d e f g h i j k l m n o p q r s ...  "
        expected = " a b c d e f g h i j k l m n o p q r s ... "
        assert expected == normalize_whitespace(string)

def test_normalize_non_break_spaces(self):
        string = "\u00A0\t €\u202F \t"
        expected = " € "
        assert expected == normalize_whitespace(string)

def text(self):
        text = "".join(self.text_nodes)
        return normalize_whitespace(text.strip())

def append_text(self, text):
        text = normalize_whitespace(text)
        self.text_nodes.append(text)
        return text