def get_token_network_identifiers(
        chain_state: ChainState,
        payment_network_id: PaymentNetworkID,
) -> List[TokenNetworkID]:
    """ Return the list of token networks registered with the given payment network. """
    payment_network = chain_state.identifiers_to_paymentnetworks.get(payment_network_id)

    if payment_network is not None:
        return [
            token_network.address
            for token_network in payment_network.tokenidentifiers_to_tokennetworks.values()
        ]

    return list()
Return the list of token networks registered with the given payment network.