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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 add_filter_by_date(self, query, out_params):
 """Applies the filter by Requested date to the search query """

        date_query = formatDateQuery(self.context, 'Requested')
        if date_query:
            query['created'] = date_query
            requested = formatDateParms(self.context, 'Requested')
            out_params.append({'title': _('Requested'),
                               'value': requested,
                               'type': 'text'})