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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 areasAndLengths(self, polygons, lengthUnit, areaUnit, calculationType, ):
 """ The areasAndLengths operation is performed on a geometry service resource. This operation calculates areas and perimeter lengths for each polygon specified in the input array. Inputs: polygons - The array of polygons whose areas and lengths are to be computed. lengthUnit - The length unit in which the perimeters of polygons will be calculated. If calculationType is planar, then lengthUnit can be any esriUnits constant. If lengthUnit is not specified, the units are derived from sr. If calculationType is not planar, then lengthUnit must be a linear esriUnits constant, such as esriSRUnit_Meter or esriSRUnit_SurveyMile. If lengthUnit is not specified, the units are meters. For a list of valid units, see esriSRUnitType Constants and esriSRUnit2Type Constant. areaUnit - The area unit in which areas of polygons will be calculated. If calculationType is planar, then areaUnit can be any esriUnits constant. If areaUnit is not specified, the units are derived from sr. If calculationType is not planar, then areaUnit must be a linear esriUnits constant such as esriSRUnit_Meter or esriSRUnit_SurveyMile. If areaUnit is not specified, then the units are meters. For a list of valid units, see esriSRUnitType Constants and esriSRUnit2Type constant. The list of valid esriAreaUnits constants include, esriSquareInches | esriSquareFeet | esriSquareYards | esriAcres | esriSquareMiles | esriSquareMillimeters | esriSquareCentimeters | esriSquareDecimeters | esriSquareMeters | esriAres | esriHectares | esriSquareKilometers. calculationType - The type defined for the area and length calculation of the input geometries. The type can be one of the following values: planar - Planar measurements use 2D Euclidean distance to calculate area and length. Th- should only be used if the area or length needs to be calculated in the given spatial reference. Otherwise, use preserveShape. geodesic - Use this type if you want to calculate an area or length using only the vertices of the polygon and define the lines between the points as geodesic segments independent of the actual shape of the polygon. A geodesic segment is the shortest path between two points on an ellipsoid. preserveShape - This type calculates the area or length of the geometry on the surface of the Earth ellipsoid. The shape of the geometry in its coordinate system is preserved. Output: JSON as dictionary """

        url = self._url + "/areasAndLengths"
        params = {
            "f" : "json",
            "lengthUnit" : lengthUnit,
            "areaUnit" : {"areaUnit" : areaUnit},
            "calculationType" : calculationType
        }
        if isinstance(polygons, list) and len(polygons) > 0:
            p = polygons[0]
            if isinstance(p, Polygon):
                params['sr'] = p.spatialReference['wkid']
                params['polygons'] = [poly.asDictionary for poly in polygons]
            del p
        else:
            return "No polygons provided, please submit a list of polygon geometries"
        return self._get(url=url, param_dict=params,
                            securityHandler=self._securityHandler,
                            proxy_url=self._proxy_url,
                           proxy_port=self._proxy_port)