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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 _read_reported(msg_db):
 """Retrieve a list of directories previous reported. """

    reported = []
    if os.path.exists(msg_db):
        with open(msg_db) as in_handle:
            for line in in_handle:
                reported.append(line.strip())
    return reported