If you are trying to write a paper and this string is a you encountered, please clarify the following:

Where did you encounter "2sl.7z"? If it was a file you downloaded, it may be a corrupted or specifically named archive that requires 7-Zip or a similar utility to open. Your Goal: 0001104659-19-061218.txt - SEC.gov

Are you writing about computer science (compression algorithms), finance (SEC filings), or another field?