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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 all_files_in_directory(path):
 """ Recursively ist all files under a directory """

    file_list = []
    for dirname, dirnames, filenames in os.walk(path):
        for filename in filenames:
            file_list.append(os.path.join(dirname, filename))
    return file_list