ABSTRACT
Learning goal: You can compose images from geometrical shapes and text. 18.1 IN THIS CHAPTER YOU WILL LEARN
• How to draw images with the Python Imaging Library
• How to draw a schematic image of a plasmid
• How to draw geometrical shapes
• How to add text to an image
• How to combine several pictures to a single image
• How to resize an image
• How to convert a color image to a black-and-white image
18.2 STORY: PLOT A PLASMID One of the rst articial plasmids was constructed in 1977 by Francisco Bolivar and Raymond Rodriguez. It consists of 4,361 DNA base pairs, a replication origin, a gene for ampicillin resistance, and one gene for tetracycline resistance. e plasmid contains many restriction sites and thus serves as a base for constructing genetic vectors.