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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_last_modified_date(filename):
 """ Get the last modified date of a given file :param filename: string: pathname of a file :return: Date """

    if os.path.isfile(filename):
        t = os.path.getmtime(filename)
        return datetime.date.fromtimestamp(t).strftime('%d/%m/%Y')
    return None