updated for version 7.4.609 Problem: For complicated list and dict use the garbage collector can run out of stack space. Solution: Use a stack of dicts and lists to be marked, thus making it iterative instead of recursive. (Ben Fritz)

1 changed line 1
scalar test OK
2 line 2
dictionary with list OK
circular test OK
[123.0, 'abc', [1, 2, 3], {'a': 1, 'b': 2, 'c': 3}]
{'4': 123.0, '5': 'abc', '6': [1, 2, 3], '7': {'a': 1, 'b': 2, 'c': 3}}