@classmethod
    def _size_selector(cls, possible_sizes):
        """Select the maximum size, utility function for adding borders.

        The number two is used so that the edges of a column have spaces
        around them (instead of being right next to a column separator).

        :param possible_sizes: possible sizes available
        :returns: maximum size
        :rtype: number
        """
        try:
            return max(x + 2 for x in possible_sizes)
        except __HOLE__:
            return 0
dataset/ETHPy150Open openstack/taskflow/taskflow/types/table.py/PleasantTable._size_selector