I am currently learning Blender on Ubuntu 18.04 for openFOAM meshing. I was going through a tutorial today and the error in the image came up when I clicked on "Build" in the swiftBlock tab. Not entirely sure how to proceed.[![enter image description here](https://i.stack.imgur.com/aWTXY.png)](https://i.stack.imgur.com/aWTXY.png)

Thanks in advance.