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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 rank_dated_files(pattern, dir, descending=True):
 """Search a directory for files that match a pattern. Return an ordered list of these files by filename. Args: pattern: The glob pattern to search for. dir: Path to directory where the files will be searched for. descending: Default True, will sort alphabetically by descending order. Returns: list: Rank-ordered list by filename. """

    files = glob.glob(op.join(dir, pattern))
    return sorted(files, reverse=descending)