Django：ChoiceField选项隐藏在模板中

Question

在django应用程序的表单中使用ChoiceField时， 选项和“选择”标记显示在源代码（检查器）中，而不显示在页面中。

使用CharField时不会发生此问题。

我从模型中得到选择，但是即使手动设置选择，问题仍然存在。

这里是Forms.py：

from django import forms
from .models import Placard, Agent

class FormDossier(forms.Form):

    j = 0
    placard_options = []
    agent_options = []

    for i in Placard.objects.all().order_by('rang'):
        tup = str(j), i.rang
        placard_options.append(tup)
        j=j+1

    for i in Agent.objects.all().order_by('numero_de_somme'):
        tup = str(j), i.numero_de_somme
        agent_options.append(tup)
        j=j+1

    f_agent = forms.ChoiceField(widget=forms.Select, choices=agent_options,label = "رقم التأجير" )
    f_placard = forms.ChoiceField(widget=forms.Select, choices=placard_options,label = "الخزانة")
    f_tiroir = forms.CharField(label = "الرف")

View.py

def CreateDossier(request): 
    form = FormDossier(request.POST or None)
    if form.is_valid():
        _p = form.cleaned_data['f_placard']
        _a = form.cleaned_data['f_agent']
        t = form.cleaned_data['f_tiroir']

        p = Placard.object.get(rang=_p)
        a = Agent.object.get(numero_de_somme=_a)

        Dossier(agent=a, placard=p, tiroir=t)

        return HttpResponseRedirect('/')

return render(request, 'dossier/create.html', locals())

模板

<div class="row">
    <form method="post" class="col s12">
        <div class="row">

            {% csrf_token %}
            {{ form.as_p }}
        </div>
    </form>
</div>