func: function updatePriceFromRealUnicornPrice() {
      require(block.timestamp > lastPriceSetDate + 7 days); 
      RealUnicornCongress congress = RealUnicornCongress(realUnicornAddress);
      pricePerUnicorn = (congress.priceOfAUnicornInFinney() * 1 finney) / 1000;
      PriceUpdate(pricePerUnicorn, msg.sender);
    }