Django DetailView with pagination for related objects

This is an example of a DetailView of a User that can have a paginated list of Purchases:

from django.views.generic.detail import DetailView
from django.core import paginator

@method_decorator(staff_member_required(login_url='user_login'), name='dispatch')
class UserDetailView(DetailView):
    model = User
    template_name = "user_detail.html"
    purchases_paginate_by = 5

    def get_context_data(self, **kwargs):
        context = super(UserDetailView, self).get_context_data(**kwargs)

        purchases_page = self.request.GET.get("purchases_page")
        purchases = self.object.get_purchases().filter()
        purchases_paginator = paginator.Paginator(purchases, self.purchases_paginate_by)
        # Catch invalid page numbers
        try:
            purchases_page_obj = purchases_paginator.page(purchases_page)
        except (paginator.PageNotAnInteger, paginator.EmptyPage):
            purchases_page_obj = purchases_paginator.page(1)

        context["purchases_page_obj"] = purchases_page_obj
        return context

In the template file, the pagination needs to done similar to the following example (using django-bootstrap3):

{% bootstrap_pagination purchases_page_obj extra=request.GET.urlencode parameter_name="purchases_page" %}

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