Python and creating svn_client_ctx_t object

I've just upgraded from 0.17.1 to r4907 and I ran into problems while
updating one of my python scripts which calls svn_client_export to the
new svn_client_ctx_t interface.

After looking through the include headers I cannot find an obvious way
to create this object in python.

-- 
Jon
  "Gentlemen! You can't fight in here, this is the War Room!"
        President Merkin Muffley, Dr. Strangelove 
          or: How I Learned To Stop Worrying And Love The Bomb