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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 values(self, column_major=False):
 """Return a nested list with the worksheet values. Args: column_major (bool):
 as list of columns (default list of rows) Returns: list: list of lists with values """

        if column_major:
            return list(map(list, zip(*self._values)))
        return [row[:] for row in self._values]