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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_wms_wcs_url_parameters(request, date):
 """ Returns parameters common dictionary for WMS and WCS request. :param request: OGC-type request with specified bounding box, cloud coverage for specific product. :type request: OgcRequest or GeopediaRequest :param date: acquisition date or None :type date: datetime.datetime or None :return: dictionary with parameters :rtype: dict """

        params = {
            'BBOX': str(request.bbox.reverse()) if request.bbox.crs is CRS.WGS84 else str(request.bbox),
            'FORMAT': MimeType.get_string(request.image_format),
            'CRS': CRS.ogc_string(request.bbox.crs),
        }

        if date is not None:
            start_date = date if request.time_difference < datetime.timedelta(
                seconds=0) else date - request.time_difference
            end_date = date if request.time_difference < datetime.timedelta(
                seconds=0) else date + request.time_difference
            params['TIME'] = '{}/{}'.format(start_date.isoformat(), end_date.isoformat())

        return params