def max_item(self):
if self.is_empty():<EOL><INDENT>raise ValueError("<STR_LIT>")<EOL><DEDENT>node = self._root<EOL>while node.right is not None:<EOL><INDENT>node = node.right<EOL><DEDENT>return node.key, node.value<EOL>
Get item with max key of tree, raises ValueError if tree is empty.