code: def forward(self, inputs):
      self.retain_inputs((0, 1))
      sp, dn = inputs
      c = _coo_matmul(
          sp,
          self.sp_row,
          self.sp_col,
          self.sp_shape,
          self.sp_order,
          dn,
          self.transa,
          self.transb,
          self.transc,
          self.dtype,
      )
      return (utils.force_array(c, self.dtype),)
  
imports: import numpy
  import chainer
  from chainer import backend
  from chainer.backends import cuda
  from chainer import function_node
  from chainer import utils
  from chainer.utils import type_check
label_desc: Use image node_id 3 for calling the CooMatMul obj's underlying member method code with example usage: obj.forward(inputs) and returns: utils