You can create a function field that returns what you need and then include that field in the view.  So, in your case, first create the method:

def partner_names(self, cr, uid, ids, name, args, context=None)

    res = {}

    for _obj in self.browse(cr, uid, ids, context=None):

      res[_obj.id] = ....

    return res

Note that the signature of the method must be as I have described and the return value must be a dictionary whose key is each id that is being processed and the value is the value to return.

In the _columns, you add:

'partner_to_names': fields.function(partner_names, type='text', string='Partner Names')

Then use the field (partner_to_names) in the view.