各位前輩，請問下拉選單可以如何做分類，我希望是在表單上先選擇地區（‘area’=北中南東），再由地區顯示會所名稱..等等來區分，最後選到場地名稱，或是簡單一點至少下拉選單可以有 “會所名稱+場地名稱”，目前只有場地名稱顯示，所以完全不知道到底是選到哪個地區的場地。

ps django 是3.2版本，小弟剛接觸python3個多月，很多都還在摸索中，請各位前輩指導，謝謝。

models.py

class Venue(models.Model):
       site_name =  models.CharField('場地名稱', max_length=12)
    activityuser = models.ForeignKey('ActivityUser',  on_delete=models.SET_NULL, null=True, blank=True)
    area =  models.CharField('地區', max_length=10)
    club_name = models.CharField('會所名稱', max_length=12)
    site_feature =  models.CharField('場地特性', max_length=10)

class VenueInstance(models.Model):
   id = models.UUIDField('編號', primary_key=True, default=uuid.uuid4, )
    venue = models.ForeignKey('Venue', on_delete=models.SET_NULL, null=True)
    activity_name = models.TextField('活動名稱', max_length=50)
    activity_attr =  models.CharField('活動屬性', max_length=10)
    activity_category =  models.CharField('活動類別',max_length=10)

views.py

def  add_venueinstance(request):
    submitted = False
    if request.method == "POST" :
        form = VenueInstanceForm(request.POST)
        if form .is_valid():
            form.save()
            return HttpResponseRedirect('/catalog/add_venueinstance?submitted=True')
    else:
            form = VenueInstanceForm
            if 'submitted' in request.GET:
                submitted = True
            return render(request, 'catalog/add_venueinstance.html', {'form':form, 'submitted':submitted})

forms.py

class   VenueInstanceForm(ModelForm):
    class Meta:
        model = VenueInstance
        fields = "__all__"
        exclude = ['space_use', 'user_service', 'report', 'message', 'status', 'borrower']
       labels = {
            'id':'編號',
            'venue':'選擇場地',
            'activity_name':'活動名稱 ',
            'activity_attr':'活動屬性',
            'activity_category':'活動類別 ',
        }
        widgets = {
            'id':forms.TextInput(attrs={'class':'form-control', }),
            'venue':forms.Select(attrs={'class':'form-control', }),,
            'activity_name':forms.TextInput(attrs={'class':'form-control', }),  'activity_attr':forms.CheckboxSelectMultiple(choices=ACTIVITY_ATTR_CHOICES,),            'activity_category':forms.CheckboxSelectMultiple(choices=ACTIVITY_CATEGORY_CHOICES,),
}          

templates

{% extends "base_generic.html" %}

{% block content %}

        <h3> 活動申請單</h3>
        <br/>
        {% if submitted %}
                    活動申請成功 !!!
        {% else %}
            <form action = "" method = POST>
                {% csrf_token %}
                <div class="form-group">
                <div class="form-group col-md-6">
                {{ form.as_p }}
                 <div class = "row">
                    <div class="col-md-8">
                        <input type = "submit" value = "送出" class = "btn btn-success">
                    </div>
                    <div class="col-md-4">
                        <a href="{% url 'venueinstances-list' %}" class = "btn btn-secondary btn-block btn-log">
                                <i class = "fas fa-stream"></i> 回上一頁
                        </a>
                    </div>
                </div>
                </div>
            </form>
        {% endif %}

{% endblock %}