9. XOR Gate Using Basic Gates

How do you plan to solve it?

// ============================================================
// Basic Gates (given)
// ============================================================
module and_gate(input a, b, output y);
    assign y = a & b;
endmodule

module or_gate(input a, b, output y);
   assign y = a | b;
endmodule

module not_gate(input a, output y);
   assign y = ~a;
endmodule

// ============================================================
// XOR Gate
// ============================================================
module xor_gate (
    input  a, b,
    output y
);
/*
  not_gate n1(w1,a);
  not_gate n2(w2,b);
  and_gate a1(w3,a,w2);
  and_gate a2(w4,b,w1);
  or_gate o1(y,w3,w4);
*/
assign y = a^b;
endmodule