Return the filter params for a specific event of a given channel.

def get_filter_args_for_specific_event_from_channel(
        token_network_address: TokenNetworkAddress,
        channel_identifier: ChannelID,
        event_name: str,
        contract_manager: ContractManager,
        from_block: BlockSpecification = GENESIS_BLOCK_NUMBER,
        to_block: BlockSpecification = 'latest',
):
    """ Return the filter params for a specific event of a given channel. """
    if not event_name:
        raise ValueError('Event name must be given')

    event_abi = contract_manager.get_event_abi(CONTRACT_TOKEN_NETWORK, event_name)

    # Here the topics for a specific event are created
    # The first entry of the topics list is the event name, then the first parameter is encoded,
    # in the case of a token network, the first parameter is always the channel identifier
    _, event_filter_params = construct_event_filter_params(
        event_abi=event_abi,
        contract_address=to_checksum_address(token_network_address),
        argument_filters={
            'channel_identifier': channel_identifier,
        },
        fromBlock=from_block,
        toBlock=to_block,
    )

    return event_filter_params