from fastapi import FastAPI from .constants import API_V1 app = FastAPI() # #2393 source-order snapshot: SNAP captures API_V1's value at THIS line ("/api/v1"). # The later `API_V1 += "/mutated"` must not retroactively change SNAP's route. SNAP = API_V1 API_V1 += "/mutated" @app.get(SNAP) async def snap_route(): return {}