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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 find_token_type(self, request):
 """Token type identification. RFC 6749 does not provide a method for easily differentiating between different token types during protected resource access. We estimate the most likely token type (if any) by asking each known token type to give an estimation based on the request. """

        estimates = sorted(((t.estimate_type(request), n)
                            for n, t in self.tokens.items()), reverse=True)
        return estimates[0][1] if len(estimates) else None