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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 send_message(self, name, level, message):
 """Post a message for a service. Args: name (string):
 The short name of the service to query level (int):
 The level of the message (info, warning, error) message (string):
 The message contents """


        if name not in self.services:
            raise ArgumentError("Unknown service name", short_name=name)

        msg = self.services[name]['state'].post_message(level, message)
        await self._notify_update(name, 'new_message', msg.to_dict())