def cursor_up(self, count=None):
        """Move cursor up the indicated # of lines in same column.
        Cursor stops at top margin.

        :param int count: number of lines to skip.
        """
        top, _bottom = self.margins or Margins(0, self.lines - 1)
        self.cursor.y = max(self.cursor.y - (count or 1), top)
Move cursor up the indicated # of lines in same column.
        Cursor stops at top margin.

        :param int count: number of lines to skip.