docs: def quick(config, mysterious=None, only_authenticated=None):
      """
      Decides whether this user is allowed to access this view or not.
  
      :param config - Decides if the setting is on globally.
      :callable_name - The function which will return the list of users which are
                       eligible for proceeding further after this action.
      """
  
      def decorator(func):
  
          @wraps(func)
          def _quick(request, *args, **kwargs):
              # Check if the request is ajax.
              is_ajax = request.is_ajax()
  
              # Check if the config is available globally and return '' or raise
              # 404 as per the nature of the request.
              if not config:
                  return _return_blank_or_raise_404(is_ajax)
              callable_name = None
              _only_authenticated = None
  
              if mysterious is not None:
                  if type(mysterious) == bool:
                      _only_authenticated = mysterious
                  else:
                      callable_name = mysterious
              elif only_authenticated is not None:
                  _only_authenticated = only_authenticated
  
              user = request.user
              if callable_name is None:
                  if (_only_authenticated is not None and
                          _only_authenticated and
                          not user.is_authenticated()):
                      return _return_blank_or_raise_404(is_ajax)
                  else:
                      return func(request, *args, **kwargs)
              else:
                  if not user.is_authenticated():
                      return _return_blank_or_raise_404(is_ajax)
                  else:
                      _callable = function_from_string(callable_name)
                      if user.id in _callable():
                          return func(request, *args, **kwargs)
                      return _return_blank_or_raise_404(is_ajax)
              return _return_blank_or_raise_404(is_ajax)
          return _quick
      return decorator