Write a python function to find the sum of squares of first n even natural numbers.
def square_Sum(n):  
    return int(2*n*(n+1)*(2*n+1)/3)
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a python function to find the sum of squares of first n even natural numbers.
def square_Sum(n):  
    return int(2*n*(n+1)*(2*n+1)/3)[/INST]assert square_Sum(2) == 20
assert square_Sum(3) == 56
assert square_Sum(4) == 120</s>