Question

python3

(3a) Write a function, frequent, with one parameter, psw, a string. If psw is in a list of
frequently used passwords ['password', '12345', 'qwerty', 'letmein', 'trustno1',
'000000', 'passw0rd'], frequent should return False; otherwise, return True. Be sure
to include at least three good test cases in the docstring.

(3b) Password Protection SecuriCorp has recently been the victim of a number of
security breaches. Internal analysis has determined that employees use simple
passwords that are too easy to guess. You have been hired to write a password
checking program. This program should contain a function passwordChecker which
takes a password and returns one of the following security regulation codes:
Ø Passwords must be at least 5 characters long
Ø Passwords must contain at least one upper case letter
Ø Passwords must contain at least two numbers
Ø Passwords may not contain the characters "E" or "e"
Ø Passwords must include at least one non-alphanumeric character.
Ø A password may not be a frequently used password: 'password', '12345',
'qwerty', 'letmein', 'trustno1', '000000', 'passw0rd'
Consultants suggest writing a separate function to test a password against each of
these conditions.

These functions could then
be called from the passwordChecker function. However, implementation details are
left to you.

reference code:

# problem 1

# problem 1a

def checklen(astring, le):

'''

(str) -> Boolean

Returns True if length of astring is at

least le characters long, else False

>>> checklen('', 1)

False

>>> checklen('four', 5)

False

>>> checklen('check', 5)

True

>>> checklen('check6', 6)

True

'''

return len(astring) >= le

# problem 1b

# empty string needs to be treated

# as a separate condition

def is_nonalnum(astring):

'''

(str) -> Boolean

Returns True if astring contains at

least one non-alphanumeric character;

returns False otherwise.

>>> is_nonalnum('')

False

>>> is_nonalnum('abc123')

False

>>> is_nonalnum('#123')

True

'''

if len(astring) == 0:

return False

else:

return not(astring.isalnum())

# problem 1c

# if vs. elif - either is ok here

# return True must be outside of for-block!

def is_noEe(astring):

'''

(str) -> Boolean

Returns True if astring does NOT

contain characters 'E' or 'e';

returns False otherwise.

>>> is_noEe('')

True

>>> is_noEe('e')

False

>>> is_noEe('CHEM 101')

False

>>> is_noEe('abcd')

True

'''

if 'E' in astring:

return False

elif 'e' in astring:

return False

else:

return True

# prolbe 1c

# different algorithm/same solution

"""

def is_noEe(astring):

'''

(str) -> Boolean

Returns True if astring does NOT

contain characters 'E' or 'e';

returns False otherwise.

>>> is_noEe('')

True

>>> is_noEe('e')

False

>>> is_noEe('CHEM 101')

False

>>> is_noEe('abcd')

True

'''

lowere = 'e' in astring

uppere = 'E' in astring

return not(lowere or uppere)

"""

# problem 1d

def is_uc_alpha(astring):

'''

(str) -> Boolean

return True if any char in s is an

uppercase letter, otherwise return False

>>> is_uc_alpha('CIS122')

True

>>> is_uc_alpha('Ducks')

True

>>> is_uc_alpha('testing')

False

'''

for c in astring:

if c.isupper():

return True

return False

# problem 1e

def is_2numbers(astring):

'''

(str) -> Boolean

returns True if astring has at least two numbers,

otherwise return False

>>> is_2numbers('CIS122')

True

>>> is_2numbers('Ducks')

False

>>> is_2numbers('ABC-1')

False

'''

digits_ctr = 0

for c in astring:

if c.isdigit():

digits_ctr += 1

return digits_ctr >= 2

# problme 1f

def is_special_char(astring):

'''

(str) -> Boolean

returns True if string contains a

special character:!, @, #, $, %, ^, &

otherwise returns False

>>> is_special_char('CIS122')

False

>>> is_special_char('CIS-122')

False

>>> is_special_char('CIS122!')

True

'''

special = '!@#$%^&'

for c in astring:

if c in special:

return True

return False

doctest.testmod()

Write the code (passwordChecker function and auxiliary functions) and execute it for
a sufficient number of test cases that SecuriCorp will be confident of their
passwords.

Answer 1

Please give the thumbs up, if it is helpful for you!!. Let me know if you have any doubts.

# -*- coding: utf-8 -*-
"""
Created on Wed Mar 7 01:32:35 2018
@author:
"""
def checklen(astring, le):
'''
(str) -> Boolean
Returns True if length of astring is at least le characters long, else False
'''
return len(astring) >= le

def is_nonalnum(astring):

'''
(str) -> Boolean
Returns True if astring contains at least one non-alphanumeric character;
returns False otherwise.
'''
if len(astring) == 0:
return False
else:
return not(astring.isalnum())

def is_noEe(astring):

'''
(str) -> Boolean
Returns True if astring does NOT contain characters 'E' or 'e';
returns False otherwise.'''
  
lowere = 'e' in astring
uppere = 'E' in astring
return not(lowere or uppere)

def is_uc_alpha(astring):

'''
(str) -> Boolean
return True if any char in s is an uppercase letter,
otherwise return False'''
for c in astring:
if c.isupper():
return True
return False

def is_2numbers(astring):

'''
(str) -> Boolean
returns True if astring has at least two numbers, otherwise return False
'''
digits_ctr = 0
for c in astring:
if c.isdigit():
digits_ctr += 1
return digits_ctr >= 2

def is_special_char(astring):

'''
(str) -> Boolean
returns True if string contains a special character:!, @, #, $, %, ^, &
otherwise returns False'''
  
special = '!@#$%^&'

for c in astring:
if c in special:
return True
return False

def frequent(psw):
'''
(str) -> Boolean
returns True if string psw contain in the list
['password', '12345', 'qwerty', 'letmein', 'trustno1','000000', 'passw0rd']
otherwise returns False'''
  
lst=['password', '12345', 'qwerty', 'letmein', 'trustno1','000000', 'passw0rd']
if psw in lst:
return False
else:
return True
  
def passwordChecker(string):
pass1=checklen(string,5)
pass2=is_nonalnum(string)
pass3=is_noEe(string)
pass4=is_uc_alpha(string)
pass5=is_2numbers(string)
pass6=is_special_char(string)
pass7=frequent(string)
  
if pass1==False:
return ("Password must be at least 5 characters long")
if pass2==False:
return ("Passwords must include at least one non-alphanumeric character.")
if pass3==False:
return ("Passwords may not contain the characters E or e")
if pass4==False:
return ("Passwords must contain at least one upper case letter")
if pass5==False:
return ("Passwords must contain at least two numbers")
if pass6==False:
return ("password must contains at least special character from [!@#$%^&]")
if pass7==False:
return ('''A password may not be a frequently used password: 'password', '12345',
'qwerty', 'letmein', 'trustno1', '000000', 'passw0rd''')
  
if pass1==True and pass2==True and pass3==True and pass4==True and pass5==True \
and pass6==True and pass7==True:
return ("\npassword meets the criteria.!!")
else:
return ("\npassword meets the criteria.!!")
  
def main():
string=input('Enter the password: ')
res=passwordChecker(string)
print(res)
  
main()

Output: