Elif and if not working or me not understanding

Question

Well my code is working, but when I type No if I want to retry to enter the password it doesn't work; it just goes to the enter password line (line 20). I have tried multiple ways to fix this but I simply cannot.

import time
import os

print ("Hello world.")
time.sleep(1)
print ("Waiting 5 seconds.")
time.sleep(5)
print ("You have waited 10 seconds.")
print ("Executing Chrome.")
time.sleep(1)
print ("Execution failed!")
password = input("Enter the execution password: ")
if password == 'password1234':
    os.system ('C:\\Users\\Harry\\AppData\\Local\\Google\\Chrome\\Application\\chrome.exe')
else:
    print ("Wrong password!")
    time.sleep(1)
    passretry = input("Do you want to try again? ")
    if passretry == 'yes' or 'Yes':
        passretry1 = input("Enter password: ") 
        if passretry1 == 'password1234':
            os.system ('C:\\Users\\Harry\\AppData\\Local\\Google\\Chrome\\Application\\chrome.exe')
    elif passretry == 'no' or 'No':
        print ("Closing...")
        time.sleep(1)
    else:
        print ("Wrong password.")
        time.sleep(.5)
        print ("Retry limit exceeded, closing.")
        time.sleep(1)

Someone needs to make a list of common Python misconceptions. The topic of `if a == x or y` would be on the top of the list. — Mark Ransom, Jan 31 '13 at 22:46
@MarkRansom: There are already a few such lists (even the FAQ sort of has one), but for some reason this doesn't seem to be on them… — abarnert, Jan 31 '13 at 23:51
@MarkRansom - it's not just python where this misconception is common — KevinDTimm, Feb 01 '13 at 13:31

score 9 · Accepted Answer · answered Jan 31 '13 at 22:39

9

if passretry == 'yes' or 'Yes':

the above if statement is evaluated as: -

if (passretry == 'yes') or 'Yes':

Now, since 'Yes' is evaluated to True, so, your if statement is always True, and hence you always have to enter new password.

You need to change the condition to: -

if passretry in ('yes', 'Yes'):

likewise, the following elif should be changed to: -

elif passretry in ('no', 'No'):

answered Jan 31 '13 at 22:39

Rohit Jain

209,639
45
409
525

@RohitJain - thanks for showing the pythonic way :) – KevinDTimm Feb 01 '13 at 13:32

score 3 · Answer 2 · answered Jan 31 '13 at 22:39

This condition:

if passretry == 'yes' or 'Yes':

means "If passretry == 'yes' is true, or 'Yes' is true". 'Yes' is always true, because a non-empty string counts as true. That's why you're always taking the first code path.

You need to spell things out a little more:

if passretry == 'yes' or passretry == 'Yes':

(Or to make your code a bit more general:

if passretry.lower() == 'yes':

which would allow for people shouting YES.)

score 2 · Answer 3 · answered Jan 31 '13 at 22:40

2

You need another complete statement:

passretry == 'yes' or passretry == 'Yes':

The string 'Yes' always evaluates to True.

answered Jan 31 '13 at 22:40

matt snider

4,013
4
24
39

Elif and if not working or me not understanding

3 Answers3

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