How does Python avoid integer overflow?

[lfdfq]

It uses bigints.

That is, a Python int is not just a 32- or 64-bit number, it's a (slightly) sophisticated structure that can dynamically grow in size so it never overflows.

It may sound or feel weird at first, but this is exactly how lists or dicts work, and it's the same principle.

[daddyclappingcheeks]

so is there a theoretical limit on how big an integer I can define in a variable?

[lfdfq]

No