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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 first(self, rows: List[Row]) -> List[Row]: """ Takes an expression that evaluates to a list of rows, and returns the first one in that list. """

        if not rows:
            logger.warning("Trying to get first row from an empty list")
            return []
        return [rows[0]]