SchedulerOutput is returned, otherwise a
tuple is returned where the first element is the sample tensor.
  Predict the sample from the previous timestep by reversing the SDE. This function propagates the sample with
the linear multistep method. It performs one forward pass multiple times to approximate the solution.  step_prk  < source > ( model_output: FloatTensor timestep: int sample: FloatTensor return_dict: bool = True  ) → SchedulerOutput 