In Odoo 16, I'm always facing the same problem with my custom modules. It occurs in random occassions when I'm adding a new field in a model, restarting the odoo service for python changes to take effect and then trying to upgrade the module in Apps. 

When I press upgrade, I get an error that the field that I just added, does not exist on the model. The field does exist in the model and no matter what I do (restarting the odoo server again, refreshing the browser) I get the same error when upgrading. The only solution is to change the name of the field. But this is not a proper solution because I have to change names of my variables and I don't want to.

What I described, doesn't always happen (e.g. as far as I've noticed, it doesn't happen when I create a new model. It only happens when I add more fields in the same model). Furthermore, I never faced the same problem with odoo 15 or 14. 

Like there is some data cached somewhere and Odoo disregards the changes I make in my python files.

Has anyone else faced the same problem? Can I somehow clean odoo cache (if something like that exists). The problem is browser independent so clearing the browser's cache didn't provide any solution.