<?xml version="1.0"?>
<xpath expr="//group//field[@name='project_id']" position="attributes">
                <attribute name="domain">['&amp;', ('allow_billable', '=', True), '&amp;',('active', '=', True), '|', ('company_id', '=', False), ('company_id', '=?', company_id)]</attribute>
            </xpath>
        