def label_from_instance(self, obj):
return str(obj)<EOL>
Return option label representation from instance.

Can be overridden to change the representation of each choice.

Example usage::

    class MyWidget(ModelSelect2Widget):
        def label_from_instance(obj):
            return str(obj.title).upper()

Args:
    obj (django.db.models.Model): Instance of Django Model.

Returns:
    str: Option label.