python - Django select how to remember choosen value? -

i have select. on item change reload page, after reloading have blank item choosen. how make remember choosen item?

teacher.html

<form id="form"  method="post">{% csrf_token %}        <select name="choose_teacher" onchange="this.form.submit();" blank_choice='please choose:' >        <option value="{{ 0 }}">blank</option>            {% item in query_results %}                <option value="{{ item.id }}">{{ item.title}} {{ item.name }} {{ item.surname }}</option>            {% endfor %}        </select> </form> {{ teacher_id }} 

views.py

def teacher(request): if request.method == 'post':     if 'choose_teacher' in request.post:         teacher_id = request.post['choose_teacher']         query_results = teacher.objects.all()         context = {'teacher_id': teacher_id,                    'query_results': query_results}         return render(request, 'planner/teacher.html', context) else:     query_results = teacher.objects.all()     context = {'query_results': query_results}     return render(request, 'planner/teacher.html', context) 

:edit:

    <form id="form" method="post">{% csrf_token %}     <select name="choose_teacher" onchange="this.form.submit();">         {% item in query_results %}             <option value="{{ item.id }}"                     {% ifequal teacher_id item.id %}selected{% endifequal %}>{{ item.title }} {{ item.name }} {{ item.surname }}</option>         {% endfor %}     </select> </form> 

change template select options to:

<option value="{{ item.id }}" {% ifequal teacher_id item.id %}selected{% endifequal %} >{{ item.title}} {{ item.name }} {{ item.surname }}</option> 

it test if the option id equal teacher_id, , add selected tag if true.

the same option 0:

<option value="0" {% ifequal teacher_id 0 %}selected{% endifequal %}>blank</option>