def max_length(self):
        l = 0

        if self.type == six.text_type:
            l = max(len(d) if d else 0 for d in self)

            if self.has_nulls():
                l = max(l, 4)  # "None"

        return l
Compute maximum length of data in this column.
dataset/ETHPy150Open wireservice/csvkit/csvkit/table.py/Column.max_length