Hii Tiago Rangel,

->If you want to run a method on updation of the module you can write that method in post-migration files.

->Follow below steps to achieve that.

1)Create folder named "migrations" inside your module.
2)Create subfolder inside it and name should be the version of the module which you have specified in the __manifest__.py file.
3)Create file named "post-migration.py"
4)Inside that file create a function like this.

def migrate(cr, version):
YOUR LOGIC HERE 

5)This method will execute once when the module updates.

->Note that if you change your manifest version,you need to create another folder with that version name and do the same process. 

->You can refer following link for your reference-https://odoo-development.readthedocs.io/en/latest/maintenance/data-migration.html

Thanks & Regards,
Email: odoo@aktivsoftware.com
Skype: kalpeshmaheshwari