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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def simple_ensure_index(request, database_name, collection_name):
 """Ensure a MongoDB index on a particular field name"""

    name = "Ensure a MongoDB index on a particular field name"

    if request.method == 'POST':
        form = EnsureIndexForm(request.POST)

        if form.is_valid():
            result = form.save(database_name, collection_name)
            messages.success(request,
                             _("Index for %s created successfully" % result))
            return HttpResponseRedirect(reverse('djmongo_show_dbs'))
        else:
            # The form is invalid
            messages.error(
                request, _("Please correct the errors in the form."))
            return render(request,
                          'djmongo/console/generic/bootstrapform.html',
                          {'form': form, 'name': name})

    else:
        # this is a GET
        context = {'name': name,
                   'form': EnsureIndexForm(
                       initial={"database_name": database_name,
                                "collection_name": collection_name})
                   }
        return render(request, 'djmongo/console/generic/bootstrapform.html',
                      context)