如何提取数据并将其替换为新代码并将其另存为新文本？ [重复]

I have been trying to extract last six numbers of an URL in each line of the original text and add it to another code that must be added to the result text. There also need to remove some code of each line from the original text and replace it with new code in the result text.I have been trying to extract last six numbers