Trying to test semantic parsing model

Hello,
I tried to test semantic parsing model but got a error as below:
> File "/home/kevinh/git/SPReID/modelx.py", line 57, in __call__
> x = self.pool(x)

> RuntimeError: Chainer's built-in function class object (AveragePooling2D) which is derived from chainer.FunctionNode has been called as if it were a callable. Use FunctionNode.apply() method instead.
> Furthermore, it's not recommended to use built-in function classes directly; use corresponding function aliases (those with snake_case name, such as F.convolution_nd) instead.

I run the code with chainer v4.2, maybe it caused the error?

In addition, whether the performance of human semantic parsing (show in Table 1 of SPReID paper) is measured with 20-class-segmentation settings, or 6-class settings?

Thanks,
Kevin