This option can be seen as a more general case of the options already available which lift the requirement of exact representation match (True for 1, normalize whitespace etc.). It would enable easier testing of relevant behavior instead of repr's artifacts.

An implementation draft is at https://github.com/tpet/cpython/commit/e59cc2d2c854f5995c36a60410eca0e893a7e269

As the expected value has to be reconstructed from the string representation anyway, it seems reasonable to do that for both values (expected and got). Only minor modifications seem to be required in that case.