py3: make sure we return strings from __str__ and __repr__...
py3: make sure we return strings from __str__ and __repr__
On Python 3:
>>> class abc:
... def __repr__(self):
... return b'abc'
...
>>> abc()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: __repr__ returned non-string (type bytes)
>>> class abc:
... def __str__(self):
... return b'abc'
...
>>> str(abc())
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: __str__ returned non-string (type bytes)
So the __str__ and __repr__ must return strings.
