Delivery tag is str while it should be bytes

According to AMQP standard delivery tag is up to 32 octets of binary data. Proton C library also has it in binary format.
But in the Python binding Delivery.tag is a string, which causes issues when trying to use it (i.e. print/visualize).

As far as I understand this is down to Swig python/cproton.i wrap_pn_delivery_tag (since typemap for pn_delivery_tag_t seems to be correct)?