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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_input_files(dirname, *ext):
 """Returns files in passed directory, filtered by extension. - dirname - path to input directory - *ext - list of arguments describing permitted file extensions """

    filelist = [f for f in os.listdir(dirname) if
                os.path.splitext(f)[-1] in ext]
    return [os.path.join(dirname, f) for f in filelist]