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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 _included_frames(frame_list, frame_format):
 """frame_list should be a list of filenames"""

    return INCLUDED_FRAMES.format(Nframes=len(frame_list),
                                  frame_dir=os.path.dirname(frame_list[0]),
                                  frame_format=frame_format)