Error every time I make a Flask Requests

Question

When I make requests from an Api to show the number of players in my template where "For in range (200)" returns the data and not the error.

<table class="cor">
                <tr class="fundo">
                    <th>Tripulante</th>
                    <th>Voo</th>
                    <th>DEP - ARR</th>
                    <th>Altitude</th>
                    <th>Velocidade</th>
                    <th>Online</th>
                    <th>Progresso</th>
                </tr>
                {% for i in range(200) %}
                    {% if "IFBR" in data[i]['DisplayName'] %}
                        <tr>
                            <td>{{data[i]['DisplayName']}}</td>
                            <td>{{data[i]['CallSign']}}</td>
                            <td>-</td>
                            <td>{{"{0:.0f} ft".format (data[i]['Altitude'])}}</td>
                            <td>{{"{0:.0f} kts".format (data[i]['Speed'])}}</td>
                            <td>Expert Server</td>
                        </tr>
                    {% endif %}
                {% endfor %}
            </table>

But when I put up 200 he’s wrong

jinja2.exceptions.UndefinedError
jinja2.exceptions.UndefinedError: list object has no element 246

Traceback (most recent call last)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1997, in __call__
return self.wsgi_app(environ, start_response)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1985, in wsgi_app
response = self.handle_exception(e)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1540, in handle_exception
reraise(exc_type, exc_value, tb)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/_compat.py", line 33, in reraise
raise value
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1982, in wsgi_app
response = self.full_dispatch_request()
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1614, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1517, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/_compat.py", line 33, in reraise
raise value
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1612, in full_dispatch_request
rv = self.dispatch_request()
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/app.py", line 1598, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/home/dalmo/Documentos/flask_IF/app/__init__.py", line 44, in expert
return render_template('index.html', data= serv_1())
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/templating.py", line 134, in render_template
context, ctx.app)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/flask/templating.py", line 116, in _render
rv = template.render(context)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/jinja2/environment.py", line 1008, in render
return self.environment.handle_exception(exc_info, True)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/jinja2/environment.py", line 780, in handle_exception
reraise(exc_type, exc_value, tb)
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/jinja2/_compat.py", line 37, in reraise
raise value.with_traceback(tb)
File "/home/dalmo/Documentos/flask_IF/app/templates/index.html", line 30, in top-level template code
{% if "IFBR" in data[i]['DisplayName'] %}
File "/home/dalmo/Documentos/flask_IF/venv/lib/python3.5/site-packages/jinja2/environment.py", line 411, in getitem
return obj[argument]
jinja2.exceptions.UndefinedError: list object has no element 246
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Answer 1

jinja2.exceptions.Undefinederror: list Object has no element 246

I believe the function fails when you try to pass a number greater than 245. That’s because the list only has 245 elements.

You can work around this problem by iterating directly under the list, without a range:

<table class="cor">
    <tr class="fundo">
        <th>Tripulante</th>
        <th>Voo</th>
        <th>DEP - ARR</th>
        <th>Altitude</th>
        <th>Velocidade</th>
        <th>Online</th>
        <th>Progresso</th>
    </tr>
    {% for element in data %}
        {% if "IFBR" in element['DisplayName'] %}
            <tr>
                <td>{{element['DisplayName']}}</td>
                <td>{{element['CallSign']}}</td>
                <td>-</td>
                <td>{{"{0:.0f} ft".format (element['Altitude'])}}</td>
                <td>{{"{0:.0f} kts".format (element['Speed'])}}</td>
                <td>Expert Server</td>
            </tr>
        {% endif %}
    {% endfor %}
</table>