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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 controllers(self):
 """Return all known controllers. Requires Telldus core library version >= 2.1.2. :return: list of :class:`Controller` instances. """

        controllers = []
        try:
            while True:
                controller = self.lib.tdController()
                del controller["name"]
                del controller["available"]
                controllers.append(Controller(lib=self.lib, **controller))
        except TelldusError as e:
            if e.error != const.TELLSTICK_ERROR_NOT_FOUND:
                raise
        return controllers