c_gtk_icon_theme_lookup_by_gicon

Undocumented in source but is binding to C. You might be able to learn more by searching the web for its name.
__gshared extern (C)
GtkIconPaintable* function(GtkIconTheme* self, GIcon* icon, int size, int scale, GtkTextDirection direction, GtkIconLookupFlags flags) c_gtk_icon_theme_lookup_by_gicon;

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