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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 updateUserRole(self, user, role):
 """ The Update User Role operation allows the administrator of an org anization to update the role of a user within a portal. Inputs: role - Sets the user's role. Roles are the following: org_user - Ability to add items, create groups, and share in the organization. org_publisher - Same privileges as org_user plus the ability to publish hosted services from ArcGIS for Desktop and ArcGIS Online. org_admin - In addition to add, create, share, and publish capabilities, an org_admin administers and customizes the organization. Example: role=org_publisher user - The username whose role you want to change. """

        url = self._url + "/updateuserrole"
        params = {
            "f" : "json",
            "user" : user,
            "role" : role
        }
        return self._post(url=url,
                             param_dict=params,
                             securityHandler=self._securityHandler,
                             proxy_url=self._proxy_url,
                             proxy_port=self._proxy_port)