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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 buffer(self, geometries, inSR, distances, units, outSR=None, bufferSR=None, unionResults=True, geodesic=True ):
 """ The buffer operation is performed on a geometry service resource The result of this operation is buffered polygons at the specified distances for the input geometry array. Options are available to union buffers and to use geodesic distance. Inputs: geometries - array of geometries (structured as JSON geometry objects returned by the ArcGIS REST API). inSR - spatial reference of the input geometries WKID. outSR - spatial reference for the returned geometries. bufferSR - WKID or a spatial reference JSON object in which the geometries are buffered. distances - distances that each of the input geometries is buffered unit - units for calculating each buffer distance. unionResults - if true, all geometries buffered at a given distance are unioned into a single (possibly multipart) polygon, and the unioned geometry is placed in the output array. geodesic - set geodesic to true to buffer the using geodesic distance. """

        url = self._url + "/buffer"
        params = {
            "f" : "json",
            "inSR" : inSR,
            "geodesic" : geodesic,
            "unionResults" : unionResults
        }
        if isinstance(geometries, list) and len(geometries) > 0:
            g = geometries[0]
            if isinstance(g, Polygon):
                params['geometries'] = {"geometryType": "esriGeometryPolygon",
                                        "geometries" : self.__geomToStringArray(geometries, "list")}
            elif isinstance(g, Point):
                params['geometries'] = {"geometryType": "esriGeometryPoint",
                                        "geometries" : self.__geomToStringArray(geometries, "list")}
            elif isinstance(g, Polyline):
                params['geometries'] = {"geometryType": "esriGeometryPolyline",
                                                        "geometries" : self.__geomToStringArray(geometries, "list")}
        else:
            return None
        if isinstance(distances, list):
            distances = [str(d) for d in distances]

            params['distances'] = ",".join(distances)
        else:
            params['distances'] = str(distances)
        params['units'] = units
        if bufferSR is not None:
            params['bufferSR'] = bufferSR
        if outSR is not None:
            params['outSR'] = outSR
        return self._get(url, param_dict=params,
                            proxy_port=self._proxy_port,
                            securityHandler=self._securityHandler,
                            proxy_url=self._proxy_url)