whether the font size is in device units or points. This field is only present for compatibility with Pango-1.8.0 (pango.types.AttrType.AbsoluteSize was added in 1.8.1); and always will be false for pango.types.AttrType.Size and true for pango.types.AttrType.AbsoluteSize.
the common portion of the attribute
size of font, in units of 1/PANGO_SCALE of a point (for pango.types.AttrType.Size) or of a device unit (for pango.types.AttrType.AbsoluteSize)
The pango.attr_size.AttrSize structure is used to represent attributes which set font size.