Create a limit order to send to exchange.
    :param float size: amount in account currency to be sent.
    :param float price: price at which the order is to be sent.
    :param str persistence_type: what happens to order at turn in play.
    :param str time_in_force: specify if it is FillOrKill/FillAndKill. This value takes precedence over any
    PersistenceType value chosen.
    :param float min_fill_size: the minimum amount to be filled for FillAndKill.
    :param str bet_target_type: Specify the type of Target, bet to certain backer profit or certain payout value.
                          Used to adjust to lower stakes if filled at better levels.
    :param float bet_target_size: Size of payout of profit to bet.

    :returns: Order information to place a limit order.
    :rtype: dict

def limit_order(price, persistence_type=None, size=None, time_in_force=None, min_fill_size=None, bet_target_type=None,
                bet_target_size=None):
    """
    Create a limit order to send to exchange.
    :param float size: amount in account currency to be sent.
    :param float price: price at which the order is to be sent.
    :param str persistence_type: what happens to order at turn in play.
    :param str time_in_force: specify if it is FillOrKill/FillAndKill. This value takes precedence over any
    PersistenceType value chosen.
    :param float min_fill_size: the minimum amount to be filled for FillAndKill.
    :param str bet_target_type: Specify the type of Target, bet to certain backer profit or certain payout value.
                          Used to adjust to lower stakes if filled at better levels.
    :param float bet_target_size: Size of payout of profit to bet.

    :returns: Order information to place a limit order.
    :rtype: dict
    """
    args = locals()
    return {
        to_camel_case(k): v for k, v in args.items() if v is not None
    }