Highlight active navbar navbar in BOOTSTRAPv.4 + Django?

Question

Django

I want to highlight the active link of the navbar by category. It seems that everything was written correctly, but in fact, when you go to one of the links, both are highlighted. I tried many options.. I don't want to create a separate method for other products)))
search_results.html

<li class="nav-item {% if search_category == BP%}active{% endif%}">
<a class="nav-link" href="{% url 'core:get_category' %}?search_item=BP">Building Products</a>
</li>
<li class="nav-item {% if search_category == BP%}active{% endif%}">
<a class="nav-link" href="{% url 'core:get_category' %}?search_item=OT">Other Products</a>
</li>

get_category in views.py method

def get_category(request):
    queryset = Item.objects.all()
    search_category = request.GET.get('search_item','')
    if search_category:
       queryset = queryset.filter(category__icontains = search_category)
    context ={
        'queryset': queryset
    }
    return render(request, 'search_results.html', context)

Conclusion when searching for Building prod

Print(search_category)
BP

Print(search_item)
<QueryDict: {'search_item': ['BP']}>

Conclusion when searching for Other products

Print(search_category)
OT

Print(search_item)
<QueryDict: {'search_item': ['OT']}>