def getBottomByPaths(paths):
 bottom = 9.876543219876543e+17
 for path in paths:
  for point in path:
   bottom = min(bottom, point.z)
 return bottom

def getBottomByPaths ( paths ) : bottom = 9.876543219876543e+17 for path in paths : for point in path : bottom = min ( bottom , point . z ) return bottom
get the bottom of the paths .