'Test the get_root function.'

def test_should_return_a_valid_top_item_on_get_root(self):

    items = self._create_top_item()
    tree_helper = BranchesTreeHelper()
    result = tree_helper.get_root(items[u'child_1'])
    self.assertEqual(items[u'top'], result)
    result = tree_helper.get_root(items[u'sub_child_2_1'])
    self.assertEqual(items[u'top'], result)
