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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 _bot_identifier(self, message):
 """Return the identifier used to address this bot in this message. If one is not found, return None. :param message: a message dict from the slack api. """


        text = message['text']

        formatters = [
            lambda identifier: "%s " % identifier,
            lambda identifier: "%s:" % identifier,
        ]
        my_identifiers = [formatter(identifier) for identifier in [self.name, self.my_mention] for formatter in formatters]

        for identifier in my_identifiers:
            if text.startswith(identifier):
                self.log.debug("sent to me:\n%s", pprint.pformat(message))
                return identifier

        return None