Check if Many2many field contains a value

[agrings]

Hello,

I'm trying to include a Partner in a category, but first I need to verify when it is in the category already. Something like this:

Partner=odoo.env['res.partner']
partner=Partner.browse(1)
if 20 not in partner.category_id:
   partner.category_id+=[20]

But the m2m field doesn't work as a list for the "in" operator.

[pedrobaeza]

AFAIK, it should be if 20 not in partner.category_id.ids:

[sebalix]

@pedrobaeza is right, you can also write this:

categ = odoo.env['category.model'].browse(20)
if categ not in partner.category_id:
    partner.category_id += categ

Does it solve your issue?

[agrings]

Perfect @sebalix and @pedrobaeza . Thank you!