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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 get_error_info(self) -> Tuple[Optional[str], Optional[str]]: """Return receiver's error tag and error message if present."""

        etag = self.find1("error-app-tag")
        emsg = self.find1("error-message")
        return (etag.argument if etag else None, emsg.argument if emsg else None)