with Odoo 14, I'm getting this error message

psycopg2.errors.SyntaxError: syntax error at or near ")"
LINE 11:             WHERE U.partner_id IN () AND U.active = 't'

when trying to create a model that extends res.partner, like this

class ModelName(models.Model):
    _inherits = {'res.partner' : 'partner_id'}
    _name = 'someName'
    _description = 'SomeDescription'

    partner_id = fields.Many2one(
        'res.partner',
        ondelete='cascade'
    )

    birthDate = fields.Date(string="Birth Date")
    place_of_birth = fields.Char(string="Place of Birth")

what's wrong with my extension ?