When bpo-12015 got resolved by increasing the length of the
random string generated by _RandomNameSequence from six to eight
characters, the docstring of the class was not adjusted accordingly.
class _RandomNameSequence:
"""An instance of _RandomNameSequence generates an endless
sequence of unpredictable strings which can safely be incorporated
- into file names. Each string is six characters long. Multiple
+ into file names. Each string is eight characters long. Multiple
threads can safely use the same instance at the same time.
_RandomNameSequence is an iterator."""