Generate a video on Replicate using hosted open-source video models (Kling, Hunyuan, LTX Video, Wan, and others) via the Replicate API. Triggers on "run a video model on Replicate", "Kling video", "Hunyuan video", "LTX video", "text-to-video Replicate", "generate a video with an open-source model". Polls the prediction and saves the MP4.