This is effecting IronPython as well, because .NET objects return copies not references. If a .NET assembly method is called from IronPython, its return is a copy, not a reference. Therefore the reference of a boolean return is not the same as the internal Python reference for that boolean, and the JSON encoder doesn't recognize the value as a boolean, but instead  treats it as an integer, and returns `str(o)`, which for `True` is "True" and for `False` is "False". Then the decoder can't interpret the JSON object because true and false are capitalize, which is not in its spec. :(

See my comment https://github.com/IronLanguages/main/issues/1033.

The patch would solve this problem. A copy of a boolean will be equal to  its value, ie False == False even if their references are not the same.