forms.Form with class in html-rendering

Heiho,

I wrote a class in views.py

class UploadFileForm(forms.Form):      file = forms.FileField()    and I use it in a function like    def import_data(request):      if request.method == "POST":          form = UploadFileForm(request.POST,                                request.FILES)  [...]     return render(        request,        'import_form.html',       {          'form': form,  	[...]    in my template import_form.html I embedded with    {{ form }}    It renders to    <th><label for="id_file">File:</label></th><td><input type="file" name="file" required id="id_file"></td>    All fine, all things do what they should do.    But I want to insert in this rendering such thing like class="btn btn-info", so it would render   <input type="file" class="btn btn-info" name="file" required id="id_file">.    How is it possible? I wasn't able to find anything in the documentation.    Thanks for your help,    bengoshi