how to change the names of all files in a directory python code example

Example 1: C# get all files in directory

//path is the path of the directory to get files from
//searchPattern is to get specific files. If you want only exe files you enter *.exe

private static IEnumerable<string> GetAllFiles(string path, string searchPattern)
        {
            return Directory.EnumerateFiles(path, searchPattern).Union(
            Directory.EnumerateDirectories(path).SelectMany(d =>
            {
                try
                {
                    return GetAllFiles(d, searchPattern);
                } catch(Exception e)
                {
                    return Enumerable.Empty<string>();
                }
            }));
        }

Example 2: append a string in all files name linux

rename 's/^/1_/' *

where ^ is for starting of the file or end