Prepare rows content to be displayed.

def prepare_rows(self,
                     rows,
                     indent,
                     has_header):

        '''Prepare rows content to be displayed.'''

        out = []

        def row_wrapper(row):
            new_rows = [
                self.wrapfunc(item).split('\n')
                for item in row
            ]
            rows = []
            for item in map(lambda *args: args, *new_rows):
                if isinstance(item, (tuple, list)):
                    rows.append([substr or '' for substr in item])
                else:
                    rows.append([item])
            return rows

        logical_rows = [
            row_wrapper(row)
            for row in rows
        ]

        columns = map(lambda *args: args, *reduce(operator.add, logical_rows))

        max_widths = [
            max([len(six.text_type(item)) for item in column])
            for column in columns
        ]
        row_separator = self.row_delimiter * (len(self.prefix) + len(self.suffix) + sum(max_widths) +
                                              len(self.delim) * (len(max_widths) - 1))

        justify = self._JUSTIFY_MAP[self.justify.lower()]

        if self.separate_rows:
            out.append(
                self.ustring(
                    indent,
                    self.LIGHT_GRAY,  # pylint: disable=no-member
                    row_separator
                )
            )
        for physical_rows in logical_rows:
            for row in physical_rows:
                line = self.prefix \
                        + self.delim.join([
                                justify(six.text_type(item), width)
                                for (item, width) in zip(row, max_widths)
                        ]) + self.suffix
                out.append(
                    self.ustring(
                        indent,
                        self.WHITE,  # pylint: disable=no-member
                        line
                    )
                )
            if self.separate_rows or has_header:
                out.append(
                    self.ustring(
                        indent,
                        self.LIGHT_GRAY,  # pylint: disable=no-member
                        row_separator
                    )
                )
                has_header = False
        return out