Something went wrong with the update of pydoc_data topics for 3.4.1rc1. As can be seen in http://hg.python.org/releasing/3.4.1/rev/c67a19e11a71, the values for the topics dict should be strings but were updated as bytes. This causes pydoc topics searches to fail. The process problem needs to be fixed for 3.4.1 final.
An example:
$ /usr/local/bin/pydoc3.4 def
Traceback (most recent call last):
File "/usr/local/bin/pydoc3.4", line 5, in <module>
pydoc.cli()
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/pydoc.py", line 2580, in cli
help.help(arg)
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/pydoc.py", line 1860, in help
elif request in self.keywords: self.showtopic(request)
File "/Library/Frameworks/Python.framework/Versions/3.4/lib/python3.4/pydoc.py", line 1941, in showtopic
pager(doc.strip() + '\n')
TypeError: can't concat bytes to str