mac x86_64 is not work

[luzexi]

When I use import('Assembly-CSharp') to import the class what I write in unity3d like:

import('Assembly-CSharp')
local tt = SomeClass()
tt.testlog()

it is not work and have an error:
LuaScriptException: [string "chunk"]:5: attempt to call global 'SomeClass' (a nil value)
NLua.Lua.ThrowExceptionFromError (Int32 oldTop) (at Assets/NLua/NLua/Lua.cs:371)
NLua.Lua.DoString (System.String chunk, System.String chunkName) (at Assets/NLua/NLua/Lua.cs:503)
HelloLua.Start () (at Assets/NLua/Examples/01_HelloLua/HelloLua.cs:30)

How can I do to call my class in lua?
My computer is macbook x86_64.