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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def get_valid_directory_list(input_directory):
 """ Get a list of folders """

    valid_input_directories = []
    for directory in os.listdir(input_directory):
        if os.path.isdir(os.path.join(input_directory, directory)):
            valid_input_directories.append(directory)
        else:
            print("{0} not a directory. Skipping ...".format(directory))
    return valid_input_directories