def METHOD_NAME(self):
    group = self.groups[0]
    another_group = self.groups[1]
    not_required_field = self.form.fields['f']
    assert not_required_field.required is False
    widget_output = not_required_field.widget.render(
        'f', self._ct_pk(group))
    selected_option = '<option value="{ct_pk}" selected="selected">{value}</option>'.format(
        ct_pk=self._ct_pk(group), value=str(group))
    selected_option_a = '<option value="{ct_pk}" selected>{value}</option>'.format(
        ct_pk=self._ct_pk(group), value=str(group))
    unselected_option = '<option value="{ct_pk}">{value}</option>'.format(
        ct_pk=self._ct_pk(another_group), value=str(another_group))
    assert selected_option in widget_output or selected_option_a in widget_output, widget_output
    assert unselected_option not in widget_output