library String {
    /**
     * @dev determine if strings are equal
     * @param _str1 strings
     * @param _str2 strings
     * @return bool
     */
    function compareStr(string memory _str1, string memory _str2)
        internal
        pure
        returns(bool)
    {
        if(keccak256(abi.encodePacked(_str1)) == keccak256(abi.encodePacked(_str2))) {
            return true;
        }
        return false;
    }
}
/**
 * @title String
 * @dev This integrates the basic functions.
 */
function compareStr(string memory _str1, string memory _str2)
    internal
    pure
    returns(bool)
{
    if(keccak256(abi.encodePacked(_str1)) == keccak256(abi.encodePacked(_str2))) {
        return true;
    }
    return false;
}

/**
 * @dev determine if strings are equal
 * @param _str1 strings
 * @param _str2 strings
 * @return bool
 */