def __repr__(self):
        return "<Requirement(package={package}, version='{version}')>".format(
            package=self.package, version=self.version)
def on_select_row(self, treeview=None):
        """When a row is selected, displays the corresponding editing panel

        @var treeview: not used
        """
        self.dialog.on_backend_selected(self.get_selected_backend_id())