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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:
 async def _registration_completed(self, message):
 """ We're connected and registered. Receive proper nickname and emit fake NICK message. """

        if not self.registered:
            # Re-enable throttling.
            self.registered = True
            self.connection.throttle = True

            target = message.params[0]
            fakemsg = self._create_message('NICK', target, source=self.nickname)
            await self.on_raw_nick(fakemsg)