I keep getting this error(Document type: res.users, Operation: read). Why?

<record id="my_module_rule_personal_hosts" model="ir.rule">

<field name="name">Only customers</field>

<field ref="model_res_partner" name="model_id"/>

<field name="domain_force">['|',('user_id','=',user.id), ('user_id', '=', False),('customer', '!=', False) ]</field>

<field name="groups" eval="[(4, ref('base.group_sale_salesman'))]"/>

<field name="perm_read" eval="True"/>

<field name="perm_write" eval="True"/>

<field name="perm_create" eval="True"/>

<field name="perm_unlink" eval="False"/>

</record>