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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 files_auth(request):
 """Display authentication for filecenter."""

    if "password" in request.POST:
        """
            Encrypt the password with AES mode CFB.
            Create a random 32 char key, stored in a CLIENT-side cookie.
            Create a random 32 char IV, stored in a SERVER-side session.
            Store the encrypted ciphertext in a SERVER-side session.

            This ensures that neither side can decrypt the password without
            the information stored on the other end of the request.

            Both the server-side session variables and the client-side cookies
            are deleted when the user logs out.
        """
        key = Random.new().read(32)
        iv = Random.new().read(16)
        obj = AES.new(key, AES.MODE_CFB, iv)
        message = request.POST.get("password")
        if isinstance(message, str):
            message = message.encode("utf-8")
        ciphertext = obj.encrypt(message)
        request.session["files_iv"] = base64.b64encode(iv).decode()
        request.session["files_text"] = base64.b64encode(ciphertext).decode()
        cookie_key = base64.b64encode(key).decode()

        nexturl = request.GET.get("next", None)
        if nexturl and nexturl.startswith("/files"):
            response = redirect(nexturl)
        else:
            response = redirect("files")
        response.set_cookie(key="files_key", value=cookie_key)
        if "username" in request.POST:
            request.session["filecenter_username"] = request.POST.get("username")
        return response
    else:
        return render(request, "files/auth.html", {"is_admin": request.user.member_of("admin_all")})