[Solved]-How to load data from Django to a variable for a D3 graph-d3.js

you need to return render(...) again after doing request.post.

def growth(request):
    template_name = 'dashboard/growth.html'
    parseddata = []
    context = {'growth_json': parseddata, 'success': false}

    if request.method == 'post':
        ...
        for data in parsed_json[data_input][year_input_int:]:
            growthdata['date'] = data['date']
            growthdata['value'] = data['value']
            growthdata['year'] = data['year']
            parseddata.append(growthdata.copy())

        context.update({'success': true})
        return render(request, template_name, context) # here
    return render(request, template_name, context)

and in your template;

{% if success %}
  {{ growth_json }}
{% endif %}