There are three ways to use this web app.

1) paste two files, press compare.
2) for gists with single files.
use notation [../webdiff/3482451-3487958 ], press compare.
3) for multi-file gists:
use notation [../webdiff/3527642>file_00_file_01.py&3527642>file_0001_file_02.py ], press compare.

for more info and source visit the readme
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