title: DataSnapshot' is declared but its value is never read.ts(6133)
body: <p>i am trying to import in visual studio code, but it giving this error <code>import { DataSnapshot } from 'firebase-functions/lib/providers/database';</code> <code>DataSnapshot' is declared but its value is never read.ts(6133)</code></p>
  
  <p><a href="https://i.stack.imgur.com/A6tVZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/A6tVZ.png" alt="enter image description here"></a></p>
  
  <p>here is full code of my index.ts, there is red line under datasnapshot and in error object</p>
  
  <pre><code>exports.sendNotificationOnAssignmentCreated = functions.database.ref('/VoltaCoin/Notifications/{user_id}').onCreate((data, context) =&gt;{
  
  const id = context.params.id;
  const eventId = context.eventId;
  const user_id = context.params.user_id;
  console.log('here is fid 22 ', user_id);
  
  
  const payload = {
      notification:{
          title : "You are now assigned",
          body : "New Assignment",
          icon : "default",
          sound : "default"
      }
  };
  
  
  var db = admin.database();
  var ref = db.ref("/IWFM/Assignments/Olnaj/AFSM/"+user_id+'/assignTo');
  
  ref.on("value", function(snapshot) {
      var assignTo = snapshot.val();
  
      var refstaf = db.ref("/IWFM/Stafs/Olnaj/1234/"+assignTo+'/FID');
      refstaf.on("value", function(snapshot1){
          var FID = snapshot1.val();
          console.log('here is ' + FID);
          return admin.messaging().sendToDevice(FID, payload).then(response=&gt;{
              // console.log('this was the notification feature');
          });
      }, function(errorObject)
      {
          console.log("The read failed: " + errorObject.code);
      });
  
  
  }, function (errorObject) {
    console.log("The read failed: " + errorObject.code);
  });
  </code></pre>
  
  <p>please if anyone can help me to fix</p>