If one is caught in conversation with an interlocutor who refuses to take a subtle hint, one always has the option of rudely and abruptly terminating the interaction - the phrase "bugger off" comes to mind. But with a little bit of lateral thinking, such interactions can be terminated very effectively without hurting anyone's feelings.
To take two examples from my own experience - examples which arose in extremely different contexts.
1. While travelling in Sri Lanka a few months ago, I was frequently troubled by the relentless pestering of touts. This is the common experience of tourists in any public location within tourist precincts in Sri Lanka. Most tourists rapidly became very agitated under relentless pestering by touts and often resorted to extremely aggressive language to drive them away. My lateral thinking-cum-Pythonesque solution to English-language importunities from touts (touts always spoke fluent English) was to respond: "Est-que vous parlez Francais?" When the tout invariably replied to this question in apparently fluent French, I then stated (in English): "I'm sorry, but I don't speak French". I was usually able to make my getaway while the tout remained rooted to the spot in a state of puzzled bemusement (spot the deliberate redundancy).
2. I sometimes interrupt boring conversations by apparently taking a call on my spectacles-cellphone. I don't have one of these. I don't believe that they actually exist. But with the rapid growth in technology these days, my inerlocutor can't be sure that I am faking it. Simply press the arm of your spectacles close to the side of your head, answer an apparent call, and begin one side of a fake, urgent and totally engrossing telephone conversation. If your interlocutor doesn't get it straight away, hold up your free hand in the "stop" gesture and frown as you continue the fake conversation. Your pestiferous interlocutor will probably wander away as you continue the conversation - convinced that you actually have a spectacles-cellphone... or perhaps an obscure mental illness. Either way, your end is achieved.
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