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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 register_stateless_command(self, node, name, handler, *, is_allowed=None, features={namespaces.xep0004_data}):
 """ Register a handler for a stateless command. :param node: Name of the command (``node`` in the service discovery list). :type node: :class:`str` :param name: Human-readable name of the command :type name: :class:`str` or :class:`~.LanguageMap` :param handler: Coroutine function to run to get the response for a request. :param is_allowed: A predicate which determines whether the command is shown and allowed for a given peer. :type is_allowed: function or :data:`None` :param features: Set of features to announce for the command :type features: :class:`set` of :class:`str` When a request for the command is received, `handler` is invoked. The semantics of `handler` are the same as for :meth:`~.StanzaStream.register_iq_request_handler`. It must produce a valid :class:`~.adhoc.xso.Command` response payload. If `is_allowed` is not :data:`None`, it is invoked whenever a command listing is generated and whenever a command request is received. The :class:`aioxmpp.JID` of the requester is passed as positional argument to `is_allowed`. If `is_allowed` returns false, the command is not included in the list and attempts to execute it are rejected with ``<forbidden/>`` without calling `handler`. If `is_allowed` is :data:`None`, the command is always visible and allowed. The `features` are returned on a service discovery info request for the command node. By default, the :xep:`4` (Data Forms) namespace is included, but this can be overridden by passing a different set without that feature to `features`. """


        info = CommandEntry(
            name,
            handler,
            is_allowed=is_allowed,
            features=features,
        )
        self._commands[node] = info
        self._disco.mount_node(
            node,
            info,
        )