At the time of this publication, nine writeups in this node pertain to the programming language, three pertain to the genus of non-fictional snakes, one is a dictionary entry, and one pertains to the performers in Monty Python's Flying Circus.
This node is missing a critical piece of literature, namely the very origin of the word "Python!"
Ovid, Hyginus, Robert Graves, Erwin Rohde, and Karl Kerenyi have all written extensively about the creature and the myths associated with him, but the earliest known mention of the dragon-like beast Python is in the Homeric Hymn to Apollo (which Homer probably did not write).
According to the story, a serpentine monster named Python was terrorizing all of Greece, in pursuit of Leto, a lesser goddess of the dark night sky. Python was a hideous creature whose body was so vast that it could flatten entire acres of cities and fields. Its bite, breath, and presence were poisonous, radiating an evil miasma into the areas around it. The reason for its violence was that Hera was wrathful toward Leto for laying with Zeus, and Hera dictated that Leto would not be allowed to give birth to her twins (Artemis and Apollo) anywhere that the sun shines. Python pursued everywhere that Leto fled, and many smaller islands actually "swam away" from Leto's efforts to escape to them: the islands both feared the monster's carnage and destruction, and Hera's anger.
Leto finally found herself on the shore of the island Delos, and Delos did not initially flee her or turn her away, because it considered itself far too inhospitable for her to consider it a place of refuge: its terrain is forbidding to all agriculture, it lacks any real mineral resources, and its only real claim to fame at the time was a small temple to Zeus on one of its conical hills. For this very reason, Leto heaped flattery and promises on the island, swearing,
Delos, if you would be willing to be the abode of my son Phoebus Apollo and make him a rich temple –; for no other will touch you, as you will find: and I think you will never be rich in oxen and sheep, nor bear vintage nor yet produce plants abundantly. But if you have the temple of far-shooting Apollo, all men will bring you hecatombs and gather here, and incessant savour of rich sacrifice will always arise, and you will feed those who dwell in you from the hand of strangers; for truly your own soil is not rich.
—Homeric Hymn to Delian Apollo 51–60
The island accepted Leto's pleas and allowed her to shelter in its crags and caves, well out of the sunlight, so that she could finally deliver her children.
Years after this event, when Phoebus, the Greek solar deity, was still young and wanted to make a proud name for himself, he took up his golden bow and arrows and set out to slay the serpent, intending to avenge the grief it gave to his mother. Python fled Apollo's pursuit, making a line of destruction all the way to the Greek town of Delphi, on the southwestern portion of Mount Parnassus in the Phocis valley. At Delphi, Python hid himself beneath or behind the temple where the Earth-goddess Gaia kept her prophetic oracle. Normally, this would be a clever way for the serpent to take refuge, both because Python himself was sacred to Gaia (in some versions, Python was considered the hero and protector of all of Mount Parnassus), and because the temple space was considered wholly inviolable, even by other gods.
Apollo followed Python all the way to the innermost sanctuary of the temple, where the Delphic Oracle sat on her tripod beside a cleft in the mountainside, where volcanic fumes emerged to give her visions of prophecy from Gaia. He killed Python there in the temple, a dreadful crime against Gaia and her oracle. Apollo placed the Omphalos Stone, a massive boulder considered to be "the navel of the world," on the dead serpent's head, to make sure it was dead, and the rest of its corpse was left hanging out the front of the temple, rotting with dreadful odor in the intense sunlight. The town was given the secondary name Pytho, "rotting," as a result, and the oracle (who retained her status and job at the temple) was titled the Pythia, for the place name. Apollo re-appropriated the temple into his own service instead of Gaia's, and as a penance for the offense against Gaia, Apollo instituted the Pythian Games, over which he personally presided.
Some versions of the story depict two serpents instead of one- a female named Delphyne and a male named Typhon; some depict Python in Apollo's service protecting the Omphalos instead of buried under it.
The symbolism of the story has been widely debated: the monster's miasma could be related to plagues or to toxic fumes from sulfurous vents and hot springs near and beneath the temple of the Delphic oracle. Another interpretation is that Apollo's slaying of Python represents how sunlight banishes the mists which form over swampy areas overnight, and how nocturnal frogs and swamp animals retreat into hiding during the day.
The story of Saint George and the Dragon is considered to be generically the same tale type, or a related type, to the story of Python (Aarne-Thompson Index tale type 300, "The dragon slayer").