I am trying to add a condition to an exisiting domain.

I would like to not have to copy the whole thing from the parent, but just add it in the attributes, but that does not work because of the domain has the square brackets around it.

<xpath expr="//tree/field[@name='account_id']" position="attributes">

<attribute name="domain" add="('external_use','=',True)" />

</xpath>

So i end up with a value like

[('deprecated', '=', False), ('user_type_id.type', 'not in', ('receivable', 'payable'))],('external_use','=',True)

Any idea how i can fix this ? else i have to revert to copying in the whole thing. But just adding looks cleaner.