Explain plz

Question

This code checks whether a series of parentheses are in correct order or in pairs. But i didnt understand the code. Can you explain the loop part in the function
def is_balanced(input_str):
s = list()
for ch in input_str:
if ch == '(':
s.append(ch)
if ch == ')':
if not s:
return False
s.pop()
return not s
if __name__=="__main__":
input_str = input()
if is_balanced(input_str):
print(input_str, "is balanced")
else:
print(input_str, "is not balanced")

Answer 1

Ex: 1
()(())
Appended (
pop (
Append (
Append (
pop (
pop (
list it empty so returns not false i.e true
Ex: 2
())(
Append (
pop (
now its ) so
if not s: since now list is empty and condition true that means ) encountered before ( so wrong ordered should return false so it return false now..
hope this examples clears it....