haven't got any idea what that picture is George, even after enlarging it, and quoting doesn't help - give us a clue.
Oh sorry. Mort knows what it is
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It's from Jiri Menzel's 'Closely Observed Trains' which is quite possibly my favourite film of all time. You're quite right about date stamps, or official stamps anyway. It's the scene where, to the desperate envy of the young clerk who is at the centre of the story, the station guard methodically and lovingly stamps the naked bottom of the girl in the picture with each of the official stamps in turn. I would have included her very delightful bottom too but Mr Google primly failed to find a picture that encompassed it.
It was meant to relate back to the little chap in Bryn's 897 who has gone through a similar experience but presumably less willingly.