await _firestoreInstance.collection("groups").document().setData(
{
  'group_name': groupName,
  'class_name': className,
  'location': groupLocation,
  'time': groupTime,
  'date': groupDate,
  'number_in_group': 1
},);

_firestoreInstance.collection("colleges").document(collegeStudent.collegeId).collection('activeGroups').document().setData({'group_id':group});