contract ERC20Burnable is ERC20 {
   /**
    * @dev Burns a specific amount of tokens.
    * @param value The amount of token to be burned.
    */
   function burn(uint256 value) public {
       _burn(msg.sender, value);
   }

   /**
    * @dev Burns a specific amount of tokens from the target address and decrements allowance
    * @param from address The address which you want to send tokens from
    * @param value uint256 The amount of token to be burned
    */
   function burnFrom(address from, uint256 value) public {
       _burnFrom(from, value);
   }
}
/**
 * @title Burnable Token
 * @dev Token that can be irreversibly burned (destroyed).
 */
function burn(uint256 value) public {
    _burn(msg.sender, value);
}

/**
 * @dev Burns a specific amount of tokens.
 * @param value The amount of token to be burned.
 */