import bpy
import bmesh
import math
import mathutils

obj = bpy.context.edit_object
me = obj.data

bm = bmesh.from_edit_mesh(me)
cursor_location = bpy.context.scene.cursor.location

for v in bm.verts:
    v.co = cursor_location - v.co
    print(v.co)

bmesh.update_edit_mesh(me, True)