code: def computeStatisticsHistograms(self,geometry,geometryType,mosaicRule=None,
                                      renderingRule=None,pixelSize=None):
          url = self._url + "/computeStatisticsHistograms"
          params = {
              "f" : "json",
              "geometry" : geometry,
              "geometryType": geometryType
          }
          if not mosaicRule is None:
              params["mosaicRule"] = mosaicRule
          if not renderingRule is None:
              params["renderingRule"] = renderingRule
          if not pixelSize is None:
              params["pixelSize"] = pixelSize
          return self._get(url=url,
                           param_dict=params,
                           securityHandler=self._securityHandler,
                           proxy_url=self._proxy_url,
                           proxy_port=self._proxy_port)