Timing Attack on Password

A password check function has a timing side-channel. Write code to exploit it.

Vulnerable Comparison

def check_password(input_pwd, correct_pwd):
    for i in range(len(input_pwd)):
        if input_pwd[i] != correct_pwd[i]:
            return False
        time.sleep(0.01)  # Side channel!
    return len(input_pwd) == len(correct_pwd)

Measure timing to discover the password character by character.