text: from graphql import GraphQLError
  from shared.messages import UNAUTHORIZED_ERROR
  
  users_session = dict()
  
  
  def get_session(username_id):
      try:
          return users_session[username_id]
      except KeyError:
          raise GraphQLError(UNAUTHORIZED_ERROR)
  
  
  def set_session(username_id, session):
      users_session[username_id] = session
  
  
  def remove_session(username_id):
      try:
          del users_session[username_id]
      except KeyError:
          raise GraphQLError(UNAUTHORIZED_ERROR)
  