class_docstr: `DDPMScheduler` explores the connections between denoising score matching and Langevin dynamics sampling.
  
  This model inherits from [`SchedulerMixin`] and [`ConfigMixin`]. Check the superclass documentation for the generic
  methods the library implements for all schedulers such as loading and saving.
  
  Args:
      num_train_timesteps (`int`, defaults to 1000):
          The number of diffusion steps to train the model.
      beta_start (`float`, defaults to 0.0001):
          The starting `beta` value of inference.
      beta_end (`float`, defaults to 0.02):
          The final `beta` value.
      beta_schedule (`str`, defaults to `"linear"`):
          The beta schedule, a mapping from a beta range to a sequence of betas for stepping the model. Choose from
          `linear`, `scaled_linear`, or `squaredcos_cap_v2`.
      variance_type (`str`, defaults to `"fixed_small"`):
          Clip the variance when adding noise to the denoised sample. Choose from `fixed_small`, `fixed_small_log`,
          `fixed_large`, `fixed_large_log`, `learned` or `learned_range`.
      clip_sample (`bool`, defaults to `True`):
          Clip the predicted sample for numerical stability.
      clip_sample_range (`float`, defaults to 1.0):
          The maximum magnitude for sample clipping. Valid only when `clip_sample=True`.
      prediction_type (`str`, defaults to `epsilon`, *optional*):
          Prediction type of the scheduler function; can be `epsilon` (predicts the noise of the diffusion process),
          `sample` (directly predicts the noisy sample`) or `v_prediction` (see section 2.4 of [Imagen
          Video](https://imagen.research.google/video/paper.pdf) paper).
      thresholding (`bool`, defaults to `False`):
          Whether to use the "dynamic thresholding" method. This is unsuitable for latent-space diffusion models such
          as Stable Diffusion.
      dynamic_thresholding_ratio (`float`, defaults to 0.995):
          The ratio for the dynamic thresholding method. Valid only when `thresholding=True`.
      sample_max_value (`float`, defaults to 1.0):
          The threshold value for dynamic thresholding. Valid only when `thresholding=True`.
      timestep_spacing (`str`, defaults to `"leading"`):
          The way the timesteps should be scaled. Refer to Table 2 of the [Common Diffusion Noise Schedules and
          Sample Steps are Flawed](https://huggingface.co/papers/2305.08891) for more information.
      steps_offset (`int`, defaults to 0):
          An offset added to the inference steps. You can use a combination of `offset=1` and
          `set_alpha_to_one=False` to make the last step use step 0 for the previous alpha product like in Stable
          Diffusion.
code: def __len__(self):
      return self.config.num_train_timesteps
  
imports: import math
  from dataclasses import dataclass
  from typing import List, Optional, Tuple, Union
  import numpy
  import torch
  from ..configuration_utils import ConfigMixin, register_to_config
  from ..utils import BaseOutput
  from ..utils.torch_utils import randn_tensor
  from .scheduling_utils import KarrasDiffusionSchedulers, SchedulerMixin
label_desc: Use image node_id 9 for calling the DDPMScheduler obj's underlying member method code with example usage: obj.__len__() and returns: self