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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 chat_unfurl( self, *, channel: str, ts: str, unfurls: dict, **kwargs ) -> SlackResponse: """Provide custom unfurl behavior for user-posted URLs. Args: channel (str):
 The Channel ID of the message. e.g. 'C1234567890' ts (str):
 Timestamp of the message to add unfurl behavior to. e.g. '1234567890.123456' unfurls (dict):
 a dict of the specific URLs you're offering an unfurl for. e.g. {"https://example.com/": {"text": "Every day is the test."}} """

        self._validate_xoxp_token()
        kwargs.update({"channel": channel, "ts": ts, "unfurls": unfurls})
        return self.api_call("chat.unfurl", json=kwargs)