I creating gtk.CellRenderCombo object 

def make_cell_render(self):

        liststore = gtk.ListStore(str, str, str)
        tiekejai = self.db.tiekeju_names_list_with_id()
        for t in tiekejai:
            liststore.append(['aa', 'aa', 'aa'])
        self.cell = gtk.CellRendererCombo()
        self.cell.set_property('editable', True)
        self.cell.set_property('text-column', 1)
        self.cell.set_property('model', liststore)
        self.cell.connect('editing-started', self.text_editing_started)
        self.cell.connect('edited', self.cell_edited_cb)
        return self.cell
    
    def cell_edited_cb(self, cell, path, new_text): 
        
        model = self.treeview.get_model()
        iter = model.get_iter_from_string(path)
        k = self.db.tiekejo_id_by_name(new_text)
        
        if k:
            print model[path][3] # i can't see model !!!
            p = self.db.update_preke(k, str(model[path][4]))
            if p:
                model.set(iter, 3, new_text)