'#5749 - `field_name` may be used as a key in _html_output().'

def test_field_name(self):

    class SomeForm(Form, ):
        some_field = CharField()
        def as_p(self):
            return self._html_output(normal_row='<p    id="p_%(field_name)s"></p>', error_row='%s', row_ender='</p>', help_text_html='    %s', errors_on_separate_row=True)
    form = SomeForm()
    self.assertHTMLEqual(form.as_p(), '<p    id="p_some_field"></p>')
