Creating Appwrite Users Target

          usersList.$id, // userId
          ID.unique(), // targetId
          'sms', // providerType
          userPhone, // identifier
          SMS_PROVIDER_ID, // providerId (optional)
          'allUserTargetList' // name (optional)
        );```

the code for sms worked perfectly well, 

**here is my code for Push**
      ```const createPushTarget = await users.createTarget(
        usersList.$id, // userId
        ID.unique(), // targetId
        'push', // providerType
        'phone', // identifier
        PUSH_PROVIDER_ID, // providerId (optional)
        'allUserTargetList' // name (optional)
      );```

here is my issues, during the time for creating the target for `email` and `sms` i could tell what the `identifier` would be but here in creating the `PUSH` user target, i cant understand the value to pass as an `identifier` for this

please, how do i do this?