GroupDocs.Annotation for Python via .NET adds annotations, markup, and review comments to documents and images through a single, format-independent API — text markup, shapes, watermarks, image and link stamps, text fields, threaded replies, versions, and import/export — and saves the result back to the original format....are positioned with a list of Point objects that describe the region...can set colors such as font_color , underline_color , and squiggly_color...