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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def ajax_login(request):
 """ Accept a POST request to login. :param request: `django.http.HttpRequest` object, containing mandatory parameters username and password required. """

    username = request.POST['username']
    password = request.POST['password']
    user = authenticate(username=username, password=password)
    if user is not None:
        if user.is_active:
            login(request, user)
            return HttpResponse(content='Successful login',
                                content_type='text/plain', status=200)
        else:
            return HttpResponse(content='Disabled account',
                                content_type='text/plain', status=403)
    else:
        return HttpResponse(content='Invalid login',
                            content_type='text/plain', status=403)