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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 authenticated(self, user_token, **validation_context):
 """Checks if user is authenticated using token passed in argument :param user_token: string representing token :param validation_context: Token.validate optional keyword arguments """

        token = self.token_storage.get(user_token)
        if token and token.validate(user_token, **validation_context):
            return True

        return False