{
       "_id" : "foo.bar",                               // will become UUID when available
       "ns" : "foo.bar",
       "epoch" : ObjectId("58b6fd76132358839e409e47"),  // will remove when UUID becomes available
       "key" : {
           "_id" : 1
       },
       "defaultCollation" : {
           "locale" : "fr_CA"
       },
       "unique" : false,
       "refreshing" : 0
       "sequenceNumber" : 5
    }