Set Look direction using lookvector?

Help and Feedback Scripting Support
#1

CFrame.lookAt() takes a current position and target position but I have a look vector I have the player to look at how do I do that.

#2 
CFrame.lookAt(pos, pos + lookVector)

or

local right = lookVector:Cross(Vector3.yAxis)
local up = right:Cross(lookVector)
CFrame.fromMatrix(pos, right, up, -lookVector)