Updated pydoc topics.py for 3.4a3 release.
Version bump to 3.4.0a3.
Added tag v3.4.0a3 for changeset dd9cdf90a507
rename some more tests to avoid duplicate names (#19123)
Issue #5845: In site.py, only load readline history from ~/.python_history if no history has been read already.  This avoids double writes to the history file at shutdown.
Post-version release cleanup.
Merge 3.4.0a3 release changes.
Minor code improvement. Review comment by Eric V. Smith
merge from 3.3