Hi,

I think a bug was introduced in v3.12.0, it this commit: 3645e32#diff-80c3339e876a6651c796df9b6621e6c8fba7d8b168f65239753398a0441b06a9R1345

isinstance(someinteger, object) called like that is always True, because int is an instance of an object:

>>> isinstance(3, object)
True

As a result, the timeout is always changed to None at this point. This causes timeout to not be respected when for example QueryJob.exception method is called.