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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 autoComplete(self, polygons=[], polylines=[], sr=None ):
 """ The autoComplete operation simplifies the process of constructing new polygons that are adjacent to other polygons. It constructs polygons that fill in the gaps between existing polygons and a set of polylines. Inputs: polygons - array of Polygon objects. polylines - list of Polyline objects. sr - spatial reference of the input geometries WKID. """

        url = self._url + "/autoComplete"
        params = {"f":"json"}
        if sr is not None:
            params['sr'] = sr
        params['polygons'] = self.__geomToStringArray(polygons)
        params['polylines'] = self.__geomToStringArray(polylines)
        return self._get(url, param_dict=params,
                            securityHandler=self._securityHandler,
                            proxy_url=self._proxy_url,
                           proxy_port=self._proxy_port)