3. simple nesting + rebinding
4. nesting with global but no free
6. nesting plus free ref to global
7. nearest enclosing scope
8. mixed freevars and cellvars
9. free variable in method
11. unoptimized namespaces
15. scope of global statements
18. verify that locals() works
19. var is bound and free in class
20. interaction with trace function
20. eval and exec with free variables
21. list comprehension with local variables
22. eval with free variables