'Ensure that every field has it\'s own unique default instance.'

def test_ensure_unique_default_instances(self):

    class D(Document, ):
        data = DictField()
        data2 = DictField(default=(lambda : {}))
    d1 = D()
    d1.data['foo'] = 'bar'
    d1.data2['foo'] = 'bar'
    d2 = D()
    self.assertEqual(d2.data, {})
    self.assertEqual(d2.data2, {})
