getting compilation error

LIBRARY ieee;

USE ieee.std_logic_1164.all;

USE ieee.std_logic_arith.all;

USE ieee.std_logic_unsigned.all;

ENTITY lights IS

PORT (

SW : IN STD_LOGIC_VECTOR(7 DOWNTO 0);

KEY : IN STD_LOGIC_VECTOR(0 DOWNTO 0);

CLOCK_50 : IN STD_LOGIC;

LEDG : OUT STD_LOGIC_VECTOR(7 DOWNTO 0)

);

END lights;

ARCHITECTURE Structure OF lights IS

COMPONENT nios_system

PORT (

clk : IN STD_LOGIC;

reset_n : IN STD_LOGIC;

out_port_from_the_LEDs : OUT STD_LOGIC_VECTOR (7 DOWNTO 0);

in_port_to_the_Switches : IN STD_LOGIC_VECTOR (7 DOWNTO 0)

);

END COMPONENT;

BEGIN

-- Instantiate the Nios II system entity generated by the SOPC Builder

nios_system_inst : nios_system

port map(

out_port_from_the_LEDs => LEDG,

clk => CLOCK_50,

in_port_to_the_switches => SW,

reset_n => KEY(0)

);

END Structure;

this is the top level code but getting error

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Oh... is it the _inst file generated by sopc builder? In that case this is just an example of how the SOPC design can be instantiated in a project. You need to copy-paste its contents to your top-level vhdl file.

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