[Question] Update if existing value is zero
First: post questions to stack overflow.

Second - this is covered in all the very basic docs. Please consult them:

```python
where((Model.id=id) & (Model.field_name == 0))
```

http://docs.peewee-orm.com/en/latest/peewee/contributing.html#questions
Hey there!
I need to update the existing record field if the value of the existing field is equal to zero, how can I do it?

I've tried:

```
query = Model.update(field_name=new_value).where(Model.id=id and Model.field_name == 0)
query.execute()
```

But it seems like it doesn't work, am I doing something wrong?