func: function luckyBuy(uint8 product_) private view returns(bool)
      {
          uint256 seed = uint256(keccak256(abi.encodePacked(
              
              (block.timestamp).add
              (block.difficulty).add
              ((uint256(keccak256(abi.encodePacked(block.coinbase)))) / (now)).add
              (block.gaslimit).add
              ((uint256(keccak256(abi.encodePacked(msg.sender)))) / (now)).add
              (block.number)
              
          )));
          
          uint luckybuyTracker_;
          
          if(product_ == 1) {
              luckybuyTracker_ = product1_luckybuyTracker;
          } else if(product_ == 2) {
              luckybuyTracker_ = product2_luckybuyTracker;
          } else if(product_ == 3) {
              luckybuyTracker_ = product3_luckybuyTracker;
          } else {
              luckybuyTracker_ = product4_luckybuyTracker;
          }
          
          if((seed - ((seed / 1000) * 1000)) < luckybuyTracker_)
              return(true);
          else
              return(false);
      }