Function: sort
This tool belongs to the Gorilla file system. It is a simple file system that allows users to perform basic file operations such as navigating directories, creating files and directories, reading and writing to files, etc. Tool description: Sort the contents of a file line by line.
Parameters: file_name: type: string
description: The name of the file appeared at current directory to sort. 
Required parameters: file_name
Response: sorted_content: type: string
description: The sorted content of the file.