code: def get_backend():
      global BACKEND
  
      if BACKEND is None:
          try:
              import _raymarching as _backend
          except ImportError:
              from .backend import _backend
  
          BACKEND = _backend
  
      return BACKEND
  
imports: import torch
  from torch.autograd import Function
  from torch.cuda.amp import custom_bwd, custom_fwd
label_desc: Use image node_id 1 for calling a global function with example usage: get_backend() and returns: BACKEND