def render_options(self, *args):
        """Render only selected options."""
        try:
            selected_choices, = args
        except __HOLE__:  # Signature contained `choices` prior to Django 1.10
            choices, selected_choices = args
            choices = chain(self.choices, choices)
        else:
            choices = self.choices
        output = ['<option></option>' if not self.is_required else '']
        selected_choices = {force_text(v) for v in selected_choices}
        choices = {(k, v) for k, v in choices if force_text(k) in selected_choices}
        for option_value, option_label in choices:
            output.append(self.render_option(selected_choices, option_value, option_label))
        return '\n'.join(output)
dataset/ETHPy150Open applegrew/django-select2/django_select2/forms.py/HeavySelect2Mixin.render_options