class_docstr: Persistent buffer for main gradients that remains allocated between training iterations
docstr: Reset the buffer to zero.
code: def zero(self):
      """Reset the buffer to zero."""
      self.data.zero_()
  
imports: from contextlib import contextmanager
  import torch
  from nemo.utils import logging
label_desc: Use image node_id 2 for calling the GradBucket obj's underlying member method code with example usage: obj.zero() without return types