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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 _build_params(self):
 """Have no idea why wrong params order can't get data. So, use `OrderedDict` here. """

        d = OrderedDict()
        d['purpose_codes'] = 'ADULT'
        d['queryDate'] = self._valid_date
        d['from_station'] = self._from_station_telecode
        d['to_station'] = self._to_station_telecode
        return d