def test_from_db_value(self):
json_field_instance = JSONField(null=True)
value = '{"a": 1}'
# Ensure that form_db_value can be called with 5 arguments
# to be django 1.11 compatible
# https://docs.djangoproject.com/en/2.0/releases/2.0/
from_db_value = json_field_instance.from_db_value(
value, None, None, None)
self.assertEqual({'a': 1}, from_db_value)
