It will replace any attributes of the same type
on that segment and be merged with any adjoining
attributes that are identical.
This function is slower than pango.attr_list.AttrList.insert
for creating an attribute list in order (potentially
much slower for large lists). However,
pango.attr_list.AttrList.insert is not suitable for
continually changing a set of attributes since it
never removes or combines existing attributes.
Insert the given attribute into the pango.attr_list.AttrList.
It will replace any attributes of the same type on that segment and be merged with any adjoining attributes that are identical.
This function is slower than pango.attr_list.AttrList.insert for creating an attribute list in order (potentially much slower for large lists). However, pango.attr_list.AttrList.insert is not suitable for continually changing a set of attributes since it never removes or combines existing attributes.