def METHOD_NAME(self):
    department = DepartmentFactory.create()
    expression = ExpressionFactory.create()
    user = UserFactory.create()
    routing_expression = RoutingExpression(
        _expression=expression,
        _department=department,
        _user=user,
        order=1,
        is_active=True,
    )
    # User must be a member of the Department
    with self.assertRaises(ValidationError, msg=f'{user.username} is not part of department {department.name}'):
        routing_expression.save()
    # Inactivate User is not allowed
    user.profile.departments.add(department)
    user.is_active = False
    user.save()
    with self.assertRaises(ValidationError, msg=f'{user.username} is not active'):
        routing_expression.save()