code: def _im2col(x, *args, **kwargs):
      if isinstance(x, numpy.ndarray):
          return im2col_cpu(x, *args, **kwargs)
      return im2col_gpu(x, *args, **kwargs)
  
imports: import numpy
  from chainer import function_node
  from chainer.utils.conv import col2im_cpu
  from chainer.utils.conv import col2im_gpu
  from chainer.utils.conv import im2col_cpu
  from chainer.utils.conv import im2col_gpu
  from chainer.utils import type_check
label_desc: Use image node_id 3 for calling a global function with example usage: _im2col(x) and returns: im2col_gpu, im2col_cpu