Answer:Here's the completed code to check the length of a password:
valid = True
password = input("Password? ")
lengthPassword = len(password)
if lengthPassword > 20:
valid = False
elif lengthPassword < 8:
valid = False
Step-by-step explanation:
The len function is used to get the length of the password. If the length is greater than 20 or less than 8, valid is set to False. Otherwise, valid remains True.
Note that the if statement uses the comparison operators > and < to check if the length of the password is greater than 20 or less than 8, respectively.