Just
7z x file.7z.
And, why not alias 'extract=uncompress'?
$ betty extract file.7z
Betty: I don't understand. Hopefully someone will make a pull request so that one day I will understand.
$ betty uncompress file.7z
Betty: Running mkdir file && tar -zxvf file.7z -C file
gzip: stdin: not in gzip format
tar: Child returned status 1
tar: Error is not recoverable: exiting now
Just
7z x file.7z.
And, why not alias 'extract=uncompress'?