i think the challenge is that if the assert fails for whatever reason the person debugging will have to got to the source code to understand what failed  i like your doc strings and would like to see something like that in the assertion method  something like asserttrue int self delta get self ping timeout  msg  it took  delta to have connectivity after live migrate  expected timeout was  timeout format delta self delta get timeout self ping timeout the goal here would be to make any failures clear to end users of the test 