Override Standard Assert Messaging in Pytest Assert

I'm using Pytest to test some SQL queries my team runs programmatically over time.

My SQL queries are lists of JSONs - one JSON corresponds to one row of data.

I've got a function that diffs the JSON key:value pairs so that we can point to exactly which values are different for a given row. Ideally, I'd output a list of these diffs instead of the standard output of an assert statement, which ends up looking clunky and not-very-useful for the end user.