#model
class BookInstance(models.Model):
    id = models.UUIDField(primary_key=True,
                          default=uuid.uuid4,
                          help_text="Unique ID for this particular book across whole library")

    book: Book = models.ForeignKey(Book, on_delete=models.SET_NULL, null=True)
    imprint = models.CharField(max_length=200)
    LOAN_STATUS = (
        ("m", "Maintenance"),
        ("o", "On loan"),
        ("a", "Available"),
        ("r", "Reserved"),
    )
    status = models.CharField(max_length=1, choices=LOAN_STATUS, blank=True, default="m",
                              help_text='Book availability')
    due_back = models.DateField(null=True, blank=True)
    borrower = models.ForeignKey(User, on_delete=models.SET_NULL, null=True, blank=True)

    class Meta:
        ordering = ["due_back"]
        permissions = (("see_all_borrowed_books", "See all borrowed books"),)

    def __str__(self):
        return f"{self.id} ({self.book.title})"

    def display_book(self):
        return f"{self.book.title}"

    @property
    def is_overdue(self):
        if self.due_back and date.today() > self.due_back:
            return True
        else:
            return False
#view
class LoanedBooksForLibrarianListView(PermissionRequiredMixin, generic.ListView):
    model = BookInstance
    template_name = "catalog/bookinstance_list_borrowed_user.html"
    paginate_by = 10

    def get_queryset(self):
        return BookInstance.objects.filter(status__exact="o").order_by("due_back")

    permission_required = 'see_all_borrowed_books'

#через шаблонизатор проверку проходит, ссылка у юзера с праввами есть, у юзера без прав нет
{% if perms.catalog.see_all_borrowed_books %}
    <li><a href="{% url 'borrowed' %}">All Borrowed</a></li>
{% endif %}