AVL Balancing

[scbauer]

This is one of the errors that im getting

Traceback (most recent call last):
  File "<pyshell#49>", line 1, in <module>
    t.insert(5)
  File "/Users/stevenbauer/Desktop/AVL.py", line 68, in insert
    stack.append(current)
NameError: global name 'stack' is not defined