odoo-contact-addons/partner_contact_phones2/models/res_partner.py

import logging
from odoo import models, fields, api, tools

_logger = logging.getLogger(__name__)


class ResPartner(models.Model):
    _name = "res.partner"

    phone2 = fields.Char("Phone 2", unaccent=False)
    mobile2 = fields.Char("Mobile 2", unaccent=False)