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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_common_url_parameters(request):
 """ Returns parameters common dictionary for WMS, WCS and FIS request. :param request: OGC-type request with specified bounding box, cloud coverage for specific product. :type request: OgcRequest or GeopediaRequest :return: dictionary with parameters :rtype: dict """

        params = {
            'SERVICE': request.service_type.value
        }

        if hasattr(request, 'maxcc'):
            params['MAXCC'] = 100.0 * request.maxcc

        if hasattr(request, 'custom_url_params') and request.custom_url_params is not None:
            params = {**params,
                      **{k.value: str(v) for k, v in request.custom_url_params.items()}}

            if CustomUrlParam.EVALSCRIPT.value in params:
                evalscript = params[CustomUrlParam.EVALSCRIPT.value]
                params[CustomUrlParam.EVALSCRIPT.value] = b64encode(evalscript.encode()).decode()

            if CustomUrlParam.GEOMETRY.value in params:
                geometry = params[CustomUrlParam.GEOMETRY.value]
                crs = request.bbox.crs

                if isinstance(geometry, Geometry):
                    if geometry.crs is not crs:
                        raise ValueError('Geometry object in custom_url_params should have the same CRS as given BBox')
                else:
                    geometry = Geometry(geometry, crs)

                if geometry.crs is CRS.WGS84:
                    geometry = geometry.reverse()

                params[CustomUrlParam.GEOMETRY.value] = geometry.wkt

        return params