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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 delete_thumbnails(relative_source_path, root=None, basedir=None, subdir=None, prefix=None):
 """ Delete all thumbnails for a source image. """

    thumbs = thumbnails_for_file(relative_source_path, root, basedir, subdir,
                                 prefix)
    return _delete_using_thumbs_list(thumbs)