init method 
    
      
Future<void>
init(
 - String currentAtSignFromApp, 
- AtClient atClientInstanceFromApp, {
- Function? newGetAtValueFromMainApp, 
}) 
    
    
  Implementation
  Future<void> init(
    String currentAtSignFromApp, AtClient atClientInstanceFromApp,
    {Function? newGetAtValueFromMainApp}) async {
  atClientInstance = atClientInstanceFromApp;
  currentAtSign = currentAtSignFromApp;
  _allReceivedUsersList = {};
  _allReceivedUsersController =
      StreamController<Map<String, HybridModel>>.broadcast();
  if (newGetAtValueFromMainApp != null) {
    getAtValueFromMainApp = newGetAtValueFromMainApp;
  } else {
    getAtValueFromMainApp = getAtValue;
  }
  await getAllLocationData();
}