Невозможно вернуть значение в django Темплэтах, используя представление на основе классов

Question

Я новичок в Django и не очень разбираюсь в представлении на основе классов. Я пытался вернуть значение в шаблоне Django, и я не смог получить доступ к этому значению с помощью тега шаблона. Я пытался напечатать значение расстояния и длительности, которые вы видите на моем графике. html код. Вот мой код views.py

class chartView(TemplateView):
    template_name = 'chart.html'

    def calculate(self):
        self.res=requests.get('https://ipinfo.io/')
        self.data=self.res.json()
        self.current_loc=self.data['city']
        gmaps = googlemaps.Client(key='****************************') 
        my_dist = gmaps.distance_matrix(self.current_loc,'bhaktapur')['rows'][0]['elements'][0] 
        # Printing the result 
        #the variable name describes the distance and time for that bloodbank eg:-redcross,whitecross etc.
        redcross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }
        my_dist = gmaps.distance_matrix(self.current_loc,'lalitpur')['rows'][0]['elements'][0] 
        whitecross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }    
        my_dist = gmaps.distance_matrix(self.current_loc,'jorpati')['rows'][0]['elements'][0]     
        greencross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }      
        my_dist = gmaps.distance_matrix(self.current_loc,'maharajgunj')['rows'][0]['elements'][0] 
        yellowcross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }
        dist_list=[redcross,whitecross,greencross,yellowcross]

        return render(request,'chart.html',{'dist_list': dist_list})


    def get_context_data(self, **kwargs):
        context  = super().get_context_data(**kwargs)
        context["qs"]= app.objects.all()
        return context

мой код url.py

urlpatterns = [

    re_path(r'chart.html/$',views.chartView.as_view(),name="Charts"),
] 
urlpatterns += staticfiles_urlpatterns()

диаграмма. html код

{% for items in qs %}
<div class="conty">
    <canvas class="myChart"></canvas>

</div><br><br>
<div align="center">
    <table>
        <tr>
            <th>{{items.name}}</th>
            <th>{{dist_list[0]['distance']}}</th>
            <th>{{dist_list[0]['duration']}}</th>
        </tr>
    </table>
</div>

{% endfor %}

и моя ошибка

django.template.exceptions.TemplateSyntaxError: Could not parse the remainder: '[0]['duration']' from 'dist_list[0]['duration']'
[19/Feb/2020 00:32:22] "GET /chart.html/ HTTP/1.1" 500 159883

Answer 1

        <th>{{dist_list[0]['duration']}}</th>

или

        <th>{{dist_list[0].get('duration')}}</th>

вместо

        <th>{{dist_list[0][duration]}}</th>

---

Также замените функцию calculate следующим образом:

class ChartView(TemplateView):
    template_name = 'chart.html'

    def get_context_data(self, **kwargs):
        context  = super().get_context_data(**kwargs)
        context["qs"]= app.objects.all()

        res=requests.get('https://ipinfo.io/')
        data=self.res.json()
        current_loc=self.data['city']
        gmaps = googlemaps.Client(key='****************************') 
        my_dist = gmaps.distance_matrix(self.current_loc,'bhaktapur')['rows'][0]['elements'][0] 
        # Printing the result 
        #the variable name describes the distance and time for that bloodbank eg:-redcross,whitecross etc.
        redcross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }
        my_dist = gmaps.distance_matrix(self.current_loc,'lalitpur')['rows'][0]['elements'][0] 
        whitecross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }    
        my_dist = gmaps.distance_matrix(self.current_loc,'jorpati')['rows'][0]['elements'][0]     
        greencross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }      
        my_dist = gmaps.distance_matrix(self.current_loc,'maharajgunj')['rows'][0]['elements'][0] 
        yellowcross={
        'distance':my_dist['distance']['text'],
        'duration':my_dist['duration']['text']
        }
        dist_list=[redcross,whitecross,greencross,yellowcross]
        context['dist_list'] = dist_list
        return context