Are you writing about computer science (compression algorithms), finance (SEC filings), or another field?
The string "" appears to be a fragment of encoded data (specifically uuencoded or Base64-like text) rather than a recognized academic topic, software utility, or standard file archive.
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
If you are trying to write a paper and this string is a you encountered, please clarify the following: