text: from rest_framework import permissions
  from rest_framework.exceptions import PermissionDenied
  
  
  class IsMember(permissions.BasePermission):
      """
      Checks if the user is a member of the service
      """
      def has_permission(self, request, view):
          if request.user.is_authenticated() or view.get_object().free_preview:
              try:
                  is_member = request.user.is_member
              except:
                  is_member = None
  
              if is_member or view.get_object().free_preview:
                  return True
              else:
                  raise PermissionDenied("You must be a member to view this.")
          raise PermissionDenied("You must be logged in to view this.")
  