parameters: (stype, oid, sources)
return_statement: return user_list
docstring: Get users subscribed to this top-level object.
  
      :param stype: The top-level object type.
      :type stype: str
      :param oid: The ObjectId of the top-level object.
      :type oid: str
      :returns: list
      :param sources: A list of sources of the top-level object.
      :type sources: list
      :returns: list
docstring_summary: Get users subscribed to this top-level object.
docstring_tokens: Get users subscribed to this top - level object .
function: def get_subscribed_users(stype, oid, sources):
      """
      Get users subscribed to this top-level object.
  
      :param stype: The top-level object type.
      :type stype: str
      :param oid: The ObjectId of the top-level object.
      :type oid: str
      :returns: list
      :param sources: A list of sources of the top-level object.
      :type sources: list
      :returns: list
      """
  
      from crits.core.user import CRITsUser
      user_list = []
      query = { '$or': [
                         {'subscriptions.%s.id' % stype: ObjectId(oid)},
                         {'subscriptions.Source.name': { '$in': sources }}
                       ]
              }
      users = CRITsUser.objects(__raw__=query)
      for user in users:
          user_list.append(user.username)
      return user_list
function_tokens: def get_subscribed_users ( stype , oid , sources ) : from crits . core . user import CRITsUser user_list = [ ] query = { '$or' : [ { 'subscriptions.%s.id' % stype : ObjectId ( oid ) } , { 'subscriptions.Source.name' : { '$in' : sources } } ] } users = CRITsUser . objects ( __raw__ = query ) for user in users : user_list . append ( user . username ) return user_list