What should be the result from a lookat function in a right handed system?

What should be the result from a lookat function in a right handed system?

I am using python's cgkit Mat44.lookat method and I am wondering if it is
implemented correctly. I wrote the author but got no answer so far. My
question is maybe silly, but I would really like to understand what's
wrong in my program.
if I do :
camera_to_world_matrix = mat4.lookAt(eye=vec3(0,0,1), target=vec3(0,0,-3),
up=vec3(0,1,0))
world_to_camera_matrix = camera_to_world_matrix.inverse()
pos_in_camera_space = world_to_camera_matrix * vec3(0,0,-10)
In my opinion, pos_in_camera_space should equal to vec3(0,0,-11) : the
distance is 11 units between the two positions and as we are in a right
handed system, the camera look toward the negative part of the z axis.
But I get vec3(0,0,11) and I don't see why.