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- The ``PluggableAuthenticationMiddleware`` constructor accepts a
``log_stream`` argument, which is typically a file. After this
release, it can also be a PEP 333 ``Logger`` instance; if it is a
PEP 333 ``Logger`` instance, this logger will be used as the
repoze.who logger (instead of one being constructed by the
middleware, as was previously always the case). When the
``log_stream`` argument is a PEP 333 Logger object, the
``log_level`` argument is ignored.