'Ensure that we can create and update a document with Falsey PK.'

def test_falsey_pk(self):

    class Person(Document, ):
        age = IntField(primary_key=True)
        height = FloatField()
    person = Person()
    person.age = 0
    person.height = 1.89
    person.save()
    person.update(set__height=2.0)
