Question

Python Coding

1. validate_username_password(username, password, users): This function checks if a given username and password matches in the stored users dictionary. This function returns True if a match found otherwise returns False.

2. validate_existing_user(users): This function asks for username and password and checks if user provided name and password matches. It prints an informational message and returns username if it does find a match. Call validate_username_password() function to perform this validation. A user has total of three chances to validate. After trying three times the function will print another error message and returns False.

Answer 1

Python code

def validate_username_password(username,password,users):

if username in users.keys():

if users[username]==password:

return True

return False

def validate_existing_user(users):

userchances=3
i=0
while i<3:

usernameinput=input("Enter username: ")
passwordinput=input("Enter password: ")
if validate_username_password(usernameinput,passwordinput,users)==True:

print("User exists.")
return usernameinput

i=i+1

print("Invalid user.")
return False

usersdict={"user1":"passwdabc","user2":"passwdpqr"}

print(validate_username_password("user1","passwdabc",
usersdict))
print(validate_username_password("userx","passwdxxx",
usersdict))
print(validate_username_password("user1","passwd",
usersdict))

print(validate_existing_user(usersdict))

Sample output 1// check validate conditions

True                                                               

False                                                              

False                                                              

Enter username: user2                                              

Enter password: passwdpqr                                          

User exists.                                                       

user2   

Sample output 2 //check no of validations

True                                                               

False                                                              

False                                                              

Enter username: adfds                                              

Enter password: sdffdsf                                            

Enter username: jfsdf                                              

Enter password: sfddsf                                             

Enter username: user1                                              

Enter password: passwdabc                                          

User exists.                                                       

user1  

Sample output 3 //display error is invalid

True                                                               

False                                                              

False                                                              

Enter username: fsdfsd                                             

Enter password: sfds                                               

Enter username: dfdfs                                              

Enter password: sdf                                                

Enter username: sdfs                                               

Enter password: sfds                                               

Invalid user.                                                      

False