updated the readme

tools/openwebtext/README.md

@@ -26,9 +26,9 @@ python blacklist_urls.py <path to the dowloaded deduplicated URLs> <filename for
 ```
 python cleanup_dataset.py <input data file> <output cleaned data filename>
 ```
-2. Using LSH, find possible duplicates and store then in a file for later processing. This step can NOT be sharded and usually takes 12 to 24 hours for OpenWebText dataset.
+2. Using LSH, find possible duplicates and store then in a file for later processing. This step can NOT be sharded and usually takes 12 to 24 hours for OpenWebText dataset. The code supports saving and loading fingerprints for recurrent deduplications.
 ```
-python find_duplicates.py <input cleaned data file> <output possible duplicate urls filename>
+python find_duplicates.py --inputs <pairlist list of input cleaned data files and keys, e.g. cc.json cc_id news.json news_id> --output <output possible duplicate urls filename>
 ```
 3. Based on similarity measure defind inside function `is_similar` (default: 0.9), group urls that are similar. Basically, for each group, only one url we should keep and remove the rest.
 ```