How to list only sub-folders (not files) using Python

Whereas Python’s os.listdir("mydirectory") will list both sub-files and sub-directories, you can use this simple list comprehension:

parent_folder = "myfolder"
sub_directories = [
    filename for filename in os.listdir(parent_folder)
    if os.path.isdir(os.path.join(parent_folder, filename))
]

which will only list sub-directories of the parent_fodler