docstr: LightningModule hook to zero grad.
  We want this to do nothing as we are zeroing grads during the training_step.
docstr_tok: ["LightningModule","hook","to","zero","grad",".","We","want","this","to","do","nothing","as","we","are","zeroing","grads","during","the","training_step","."]
code: def optimizer_zero_grad(self, *args, **kwargs):
      """LightningModule hook to zero grad.
      We want this to do nothing as we are zeroing grads during the training_step.
      """
      pass
  
imports: from functools import partial
  from typing import Any, Optional
  import torch
  from omegaconf import DictConfig
  from pytorch_lightning import Trainer
  from torch._inductor import config
  from nemo.collections.multimodal.data.dreambooth.dreambooth_dataset import DreamBoothDataset
  from nemo.collections.multimodal.modules.stable_diffusion.distributions.distributions import DiagonalGaussianDistribution
  from nemo.collections.multimodal.parts.utils import randn_like
  from nemo.collections.nlp.data.language_modeling.megatron.data_samplers import MegatronPretrainingRandomSampler
  from nemo.collections.nlp.models.language_modeling.megatron_base_model import MegatronBaseModel
  from nemo.collections.nlp.modules.common.megatron.module import Float16Module
  from nemo.collections.nlp.parts.utils_funcs import get_last_rank
  from nemo.core.classes.common import Serialization
  from nemo.utils import logging
label_desc: Use image node_id 9 for calling the MegatronDreamBooth obj's underlying member method code with example usage: obj.optimizer_zero_grad() without return types