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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 removeAllEntitlements(self, appId):
 """ This operation removes all entitlements from the portal for ArcGIS Pro or additional products such as Navigator for ArcGIS and revokes all entitlements assigned to users for the specified product. The portal is no longer a licensing portal for that product. License assignments are retained on disk. Therefore, if you decide to configure this portal as a licensing portal for the product again in the future, all licensing assignments will be available in the website. Parameters: appId - The identifier for the application for which the entitlements are being removed. """

        params = {
            "f" : "json",
            "appId" : appId
        }
        url = self._url + "/licenses/removeAllEntitlements"
        return self._post(url=url,
                          param_dict=params,
                          proxy_url=self._proxy_url,
                          proxy_port=self._proxy_port)