         path:String,
         handler:UInt)
     {
-        let pathReference:FIRDatabaseReference = reference.child(path)
+        let pathReference:DatabaseReference = reference.child(path)
         pathReference.removeObserver(withHandle:handler)
     }
     
     func transaction(
         path:String,
-        transactionBlock:@escaping((FIRMutableData) -> (FIRTransactionResult)))
+        transactionBlock:@escaping((MutableData) -> (TransactionResult)))
     {
-        let childReference:FIRDatabaseReference = reference.child(path)
+        let childReference:DatabaseReference = reference.child(path)
         childReference.runTransactionBlock(transactionBlock)
     }
 }

        path:String,
        json:Any)
    {
        let childReference:FIRDatabaseReference = reference.child(path)
        childReference.setValue(json)
    }
    
    func removeChild(path:String)
    {
        let childReference:FIRDatabaseReference = reference.child(path)
        childReference.removeValue()
    }
    

        path:String,
        json:Any) -> String
    {
        let childReference:DatabaseReference = reference.child(path).childByAutoId()
        let childId:String = childReference.key
        childReference.setValue(json)
        
