code: def _forward_gpu_core(self, x, gy):
      col = conv.im2col_gpu(
          x,
          self.kh,
          self.kw,
          self.sy,
          self.sx,
          self.ph,
          self.pw,
          cover_all=self.cover_all,
          dy=self.dy,
          dx=self.dx,
      )
      gW = cuda.cupy.tensordot(gy, col, ((0, 2, 3), (0, 4, 5))).astype(
          self.W_dtype, copy=False
      )
      return (gW,)
  
imports: import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer.backends import intel64
  from chainer import configuration
  from chainer import function_node
  import chainer.functions
  from chainer import memory_layouts
  from chainer.utils import argument
  from chainer.utils import conv
  from chainer.utils import type_check
  import chainerx
label_desc: Use image node_id 7 for calling the Convolution2DGradW obj's underlying member method code with example usage: obj._forward_gpu_core(x, gy) and returns: gW