lest/scope currencies using currencylayer.com

[valsha]

Hi, in currencylayer.com I can use:

http://apilayer.net/api/live

    ? access_key = my_api_key
    & currencies = EUR,GBP,CAD,PLN
    & source = USD
    & format = 1

this is 1 request (1000 requests per month is free) for pairs EUR,GBP,CAD,PLN

how I can use laravel-swap to get a list/scope currencies?
right now I can use only 1 pair of currencies (USD/EUR) per request
$rate = Swap::latest('EUR/USD');

Thank you.