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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 announce_urls(self, default=[]):
 # pylint: disable=dangerous-default-value """ Get a list of all announce URLs. Returns `default` if no trackers are found at all. """

        try:
            response = self._engine._rpc.t.multicall(self._fields["hash"], 0, "t.url=", "t.is_enabled=")
        except xmlrpc.ERRORS as exc:
            raise error.EngineError("While getting announce URLs for #%s: %s" % (self._fields["hash"], exc))

        if response:
            return [i[0] for i in response if i[1]]
        else:
            return default