Write a function to find the square root of a perfect number.
import math
def sqrt_root(num):
 sqrt_root = math.pow(num, 0.5)
 return sqrt_root 
<s>[INST]<<SYS>>Given a task and its code, generate test cases for the code.<</SYS>>Write a function to find the square root of a perfect number.
import math
def sqrt_root(num):
 sqrt_root = math.pow(num, 0.5)
 return sqrt_root [/INST]assert sqrt_root(4)==2
assert sqrt_root(16)==4
assert sqrt_root(400)==20</s>