I have the following field, which is a Many2many Tags exatcly like in Employees module:

category_ids = fields.Many2many(

        'it.recruitment.freelancer.category', 'freelancer_category_rel',

        'freelancer_id', 'category_id', 

        string='Matching Positions',

        ondelete='cascade',

        default='_create_default_freelancer')

But instead of Employees, I'm using Freelancers. I've create a model to hold this tags: it.recruitment.freelancer.category. 

Now I want to every time I create a new Freelancer, the category_ids field has already the 'Freelancer' tag. 

This was my attempt:

def _create_default_freelancer(self):

        model = 'it.recruitment.freelancer.category'

        return self.env[model].search([{'name': "Freelancer"}]).id

Note: The 'Freelancer' tag is added on data.xml when you install the module.