Get all other clients that are connected to the same kernel as `client`

def get_related_clients(self, client):
        """
        Get all other clients that are connected to the same kernel as `client`
        """
        related_clients = []
        for cl in self.get_clients():
            if cl.connection_file == client.connection_file and \
              cl is not client:
                related_clients.append(cl)
        return related_clients