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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _import_lua(load_dependencies=True):
 """ Import lua and dependencies. :param load_dependencies: should Lua library dependencies be loaded? :raises: RuntimeError if Lua is not available """

        try:
            import lua
        except ImportError:
            raise RuntimeError("Lua not installed")

        lua_globals = lua.globals()
        if load_dependencies:
            Script._import_lua_dependencies(lua, lua_globals)
        return lua, lua_globals