def count_active_tables(self):
        return len([1 for count in self.alias_refcount.values() if count])
Assert an element is visible by css selector.
dataset/ETHPy150Open django/django/django/db/models/sql/query.py/Query.count_active_tables--crossover with--dataset/ETHPy150Open yourlabs/django-autocomplete-light/src/dal/test/case.py/AutocompleteTestCase.assert_visible