This question is studied by Ohshika and Potyagailo (here is [a link to the lucid, as usual, mathreview by McCullough.)][1] A more definitive result is due to [T. Delzant and L. Potyagailo][2] (which has nice references, too).


  [1]: https://www.dropbox.com/s/wtol2d4ugqs3nde/OhPo.pdf?dl=0
  [2]: http://www-irma.u-strasbg.fr/~delzant/cohopf.pdf