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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 computeStatisticsHistograms(self,geometry,geometryType,mosaicRule=None, renderingRule=None,pixelSize=None):
 """ The computeStatisticsHistograms operation is performed on an image service resource. This operation is supported by any image service published with mosaic datasets or a raster dataset. The result of this operation contains both statistics and histograms computed from the given extent. Inputs: geometry - A geometry that defines the geometry within which the histogram is computed. The geometry can be an envelope or a polygon. The structure of the geometry is the same as the structure of the JSON geometry objects returned by the ArcGIS REST API. geometryType - The type of geometry specified by the geometry parameter. The geometry type can be an envelope or polygon. Values: esriGeometryEnvelope | esriGeometryPolygon mosaicRule - Specifies the mosaic rule when defining how individual images should be mosaicked. When a mosaic rule is not specified, the default mosaic rule of the image service will be used (as advertised in the root resource: defaultMosaicMethod, mosaicOperator, sortField, sortValue). renderingRule - Specifies the rendering rule for how the requested image should be rendered. pixelSize - The pixel level being used (or the resolution being looked at). If pixel size is not specified, then pixelSize will default to the base resolution of the dataset. The raster at the specified pixel size in the mosaic dataset will be used for histogram calculation. The structure of the pixelSize parameter is the same as the structure of the point object returned by the ArcGIS REST API. In addition to the JSON structure, you can specify the pixel size with a simple comma-separated syntax. """


        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)