Ojk | Python Fiddle

# The User must beable to enter a valid password before they continue
valid_password_entered = False
# Loop until valid password is entered
while not valid_password_entered:
 #Raw input is used so that the program leaves the input and does not
 #Try and interpret it
 pass_str = raw_input('Please enter your password: ')
 # To test if the password is the rigt length
 # I have used if statement
 if len(password_str) < 6:
 print 'Password:', password_str, 'too short! It must be between 6 and 12 characters.'
 elif len(password_str) > 12:
 print 'Password:', password_str, 'too long! It must be between 6 and 12 characters.'
 else:
 # Set flags to be set when different tests succeed
 lowercase_found = 0
 uppercase_found = 0
 numeric_found = 0
 # Step through string and set flags where appropriate
 for ch in password_str:
 if ch.islower():
 lowercase_found = 1
 if ch.isupper():
 uppercase_found = 1
 if ch.isdigit():
 numeric_found = 1

# Exit early if all our flags have been set
 if lowercase_found and uppercase_found and numeric_found:
 break
 # Calculate password strength, and print out result
 password_strength = lowercase_found + uppercase_found + numeric_found

# If the password is either 1, 2 or 3, then print out valid message.
 if password_strength in range(1,4):
 print 'The password', password_str, 'is valid.'

# Now print out password strength
 if password_strength == 1:
 print 'Password', password_str, 'is a WEAK password'
 elif password_strength == 2:
 print 'Password', password_str, 'is a MEDIUM password'
 else:
 print 'Password', password_str, 'is a STRONG password'
 # Set loop variable, so that we do not ask for password again
 valid_password_entered = True
 else:
 print 'Invalid password:', password_str, 'contained neither letters or numbers!'

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