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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 setUser(request):
 """In standalone mode, change the current user"""


    if not settings.PIAPI_STANDALONE or settings.PIAPI_REALUSERS:
        raise Http404

    request.session['plugit-standalone-usermode'] = request.GET.get('mode')

    return HttpResponse('')