transaction: tr._names are actually bytes, use byte string to join them...
transaction: tr._names are actually bytes, use byte string to join them
Looks like this is never checked in the tests? But trying e.g. `print(tr)` by
hand before this change would give:
TypeError: sequence item 0: expected str instance, bytes found
Looks like tr._names are always bytes (although this isn't actually enforced,
but maybe at some point it will at least be type checked e.g. by pytype).