Test

gistfile1.py

from bson.code import Code 
map_ = Code(""" 
function() { 
   if (this.right) 
     emit('right', {total:this.time, count:1}); 
   if (!this.right && this.answer) 
     emit('wrong', {total:this.time, count:1}); 
} 
""")

reduce_ = Code(""" 
function r( who , values ){ 
  var n = { total : 0 , count : 0 }; 
  for ( var i=0; i<values.length; i++ ){ 
    n.total += values[i].total; 
    n.count += values[i].count; 
  } 
  return n; 
} 
""")

finalize = Code(""" 
function f( who , res ){ 
    res.avg = res.total / res.count; 
    return res; 
 } 
""") 
...

        result = db.PlayedQuestion.collection.map_reduce( 
          map_, reduce_, 'myoutput', 
          finalize=finalize, 
          query={'play.$id': {'$in': play_ids}, 
                 'time': {'$ne': None}, 
                 } 
        ) 
        times = {} 
        for reduction in result.find(): 
            if reduction['_id'] == 'right': 
                times['right'] = reduction['value']['avg'] 
            elif reduction['_id'] == 'wrong': 
                times['wrong'] = reduction['value']['avg']