code: public static BitfinexCurrencyPair fromSymbolString(final String symbolString) {
  		for (final BitfinexCurrencyPair currency : BitfinexCurrencyPair.values()) {
  			if (currency.toBitfinexString().equalsIgnoreCase(symbolString)) {
  				return currency;
  			}
  		}
  		throw new IllegalArgumentException("Unable to find currency pair for: " + symbolString);
  	}
docs: Construct from string
  @param symbolString
  @return