The main characteristics of pythons are large size and long length. The length of python can reach 6- 10 meter, and the live weight can reach 50-60 kilograms. They are the largest primitive non-venomous snakes in the world, with traces of bands and hind limbs. There is an obvious distance between the degenerated cutin of the hind limbs of the male snake and the degenerated cutin of the female snake, which is easy to be ignored. In addition, it has a pair of developed lungs, but advanced snakes only have 1 or 1 degenerated lungs. Python's body surface pattern is very beautiful, symmetrically arranged in large pieces like a clouded leopard, with black or white spots around the edge. The scales are smooth, the back is pale yellow, taupe or brown, and the patches on the back of the body are very irregular. Python's head is small and black, with a black spot on the back of the eye and at the moment, yellow and white under the throat, and no obvious differentiation of abdominal scales. The tail is short and thick, and it is entangled and aggressive.