import difflib
first_file = "Prebackup.txt"
second_file = "Postbackup.txt"
first_file_lines = open(first_file).readlines()
second_file_lines = open(second_file).readlines()
difference = difflib.HtmlDiff().make_file(first_file_lines, second_file_lines, first_file, second_file)
difference_report = open("Diff.html",'w')
difference_report.write(difference)
difference_report.close()
从上面的代码中，我也得到了差异，更改或新添加的行，而这些行未更改。现在我只想获得差异，请帮助我。