code: def _nextafter(x1, x2):
      with torch.no_grad():
          if hasattr(torch, "nextafter"):
              out = torch.nextafter(x1, x2)
          else:
              out = np_nextafter(x1, x2)
      return _StitchGradient.apply(x1, out)
  
imports: from enum import Enum
  import math
  import numpy
  import torch
  import warnings
  from .event_handling import combine_event_functions
label_desc: Use image node_id 16 for calling a global function with example usage: _nextafter(x1, x2) and returns: _StitchGradient