How can i use the dataset?

Hi! 
First, thank you for sharing your nice papers and codes.

Sadly, I have some difficulty to run the PRNet code.
I'm confused that how can i use the dataset obtained from ispd2005_2015.py

When I set the $dataroot as /DREAMPlace/benchmarks/ispd2005, 
I have some 'not valid directory' error.

how can i train the PRNet with ispd dataset?

thank you