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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 get(self, sid):
 """ Constructs a InstalledAddOnExtensionContext :param sid: The unique Extension Sid :returns: twilio.rest.preview.marketplace.installed_add_on.installed_add_on_extension.InstalledAddOnExtensionContext :rtype: twilio.rest.preview.marketplace.installed_add_on.installed_add_on_extension.InstalledAddOnExtensionContext """

        return InstalledAddOnExtensionContext(
            self._version,
            installed_add_on_sid=self._solution['installed_add_on_sid'],
            sid=sid,
        )