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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 getItem(self, itemId):
 """gets the refernce to the Items class which manages content on a given AGOL or Portal site. """

        url = "%s/items/%s" % (self.root, itemId)
        return Item(url=url,
                    securityHandler=self._securityHandler,
                    proxy_url=self._proxy_url,
                    proxy_port=self._proxy_port)