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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def _parse_date(date):
 """Parse from the user input `date`. e.g. current year 2016: This fn wouldn't check the date, it only gather the number as a string. """

        result = ''.join(re.findall('\d', date))
        l = len(result)

        # User only input month and day, eg 6-1, 6.26, 0626...
        if l in (2, 3, 4):
            year = str(datetime.today().year)
            return year + result

        # User input full format date, eg 201661, 2016-6-26, 20160626...
        if l in (6, 7, 8):
            return result

        return ''