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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_filename4code(module, content, ext=None):
 """Generate filename based on content The function ensures that the (temporary) directory exists, so that the file can be written. Example: filename = get_filename4code("myfilter", code) """

    imagedir = module + "-images"
    fn = hashlib.sha1(content.encode(sys.getfilesystemencoding())).hexdigest()
    try:
        os.mkdir(imagedir)
        sys.stderr.write('Created directory ' + imagedir + '\n')
    except OSError:
        pass
    if ext:
        fn += "." + ext
    return os.path.join(imagedir, fn)