Filtering of vertical pipes

Ultimately, I am trying to place valves in pipes that intersect a plumbing fixture bounding box. I am attempting to filter out entities that have any vertical change in them as that is causing for some funny looking 3D renderings.

The output I currently have is a list of pipes with Line(StartPoint…, Direction = Vector(X=0.000, Y=0.000, Z=10.000). How do you access that portion of the data in a Geometry.Line object type?

Figured it out from here:

Earlier in the script I filter by slope to remove any that have a non computed slope (horizontal is 0, vertical is Not Computed).