Ovid’s Metamorphoses Book 1 seats Apollo’s killing of the Python before the Daphne chase. A named Python foe in that poem, not serpent as a generic snake and not a programming-language joke.
Ovid’s Metamorphoses seats Apollo’s fight with Python among dragon-serpent speech in Roman poetic reception. Dragon as the great serpent being historically related to the named Python, not identity and not every wyrm.