the index of a line, which must be between 0 and <literal>pango_layout_get_line_count(layout) - 1</literal>, inclusive.
the requested PangoLayoutLine, or NULL if the index is out of range. This layout line can be ref'ed and retained, but will become invalid if changes are made to the gtk.Layout
Retrieves a particular line from a gtk.Layout
Use the faster Layout.getLineReadonly if you do not plan to modify the contents of the line (glyphs, glyph widths, etc.).