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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 search_messages(self, *, query: str, **kwargs) -> SlackResponse: """Searches for messages matching a query. Args: query (str):
 Search query. May contains booleans, etc. e.g. 'pickleface' """

        self._validate_xoxp_token()
        kwargs.update({"query": query})
        return self.api_call("search.messages", http_verb="GET", params=kwargs)