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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 _parse_weekday(val):
        ''' Try to match a day-of-week abbreviation, then try a day-of-week full name '''
        val = val.title()
        try:
            return list(calendar.day_abbr).index(val)
        except ValueError:
            try:
                return list(calendar.day_name).index(val)
            except ValueError:
                return None