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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 im_open(self, *, user: str, **kwargs) -> SlackResponse: """Opens a direct message channel. Args: user (str):
 The user id to open a DM with. e.g. 'W1234567890' """

        kwargs.update({"user": user})
        return self.api_call("im.open", json=kwargs)