Exceptions in
Python are a mechanism used to report errors (of an
exceptional variety); programs can be and are written to expect and handle
certain types of exceptions using try and except. But
exceptions were originally meant to report a single error event and, these
days, things are a tad more complicated than that. A recent Python
Enhancement Proposal (PEP) targets adding exception groups, as well as new
syntax to catch and handle the groups.

Source: LWN.net – [$] Python exception groups