# <s>Python3</s> Bash* 60 *Also other shells. Any one for which the [truthy/falsy][1] test passes on a program exit code read I python3 -c "from ipaddress import*;IPv4Address('$I')" ## Explanation The trouble with a pure Python solutions is that a program crashing is considered indeterminate. We could use a "lot" of code to convert an exception into a proper truthy/fasly value. However, at some point the Python interpreter handles this uncaught exception and returns a non-zero exit code. For the low-low cost of changing languages to your favourite Unix shell, we can save quite a bit of code! Of course, this is vulnerable to injection attacks... Inputs such as `1.1.1.1'); print('Doing Something Evil` are an unmitigated threat! [1]: https://codegolf.meta.stackexchange.com/a/2194/25088