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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 router_connections(self):
 """Return a list of MongoClients, one for each mongos."""

        clients = []
        for server in self._routers:
            if Servers().is_alive(server):
                client = self.create_connection(Servers().hostname(server))
                clients.append(client)
        return clients