Question

                      Contact Manager

COMMAND MENU

----------------------------------------------------------

list - Display all contacts

view - View a contact

add - Add a contact

del - Delete a contact

exit - Exit program

Command: list

1. Tom van Rossum

2. Edward Idle

Command: view

Number: 2

Name: Edward Idle

Email: [email protected]

Phone: +44 20 7946 0958

Command: add

Name: John Smith

Email: [email protected]

Phone: 559-123-4567

John Smith was added.

Command: list

1. Tom van Rossum

2. Edward Idle

3. John Smith

Command: exit

Bye!

Specifications

 Use the attached CSV file named contacts.csv.

 When the program starts, it should read the contacts from the CSV file.

 For the view and del commands, display an error message if the user enters an invalid

contact number.

 When you add or delete a contact, the change should be saved to the CSV file

immediately. That way, no changes are lost, even if the program crashes later.

Answer 1

import csv,os;

## add new entry to the contact file
def add(name, email, phone):
  with open('contacts.csv','a', newline='') as  csv_file:
     writter = csv.writer(csv_file, delimiter=',');
     writter.writerow([name,email,phone]);
     csv_file.close();
     print(name,"was added");

##list all  contacts present in the csv file
def list():
     contacts = [];
     with open('contacts.csv','r') as  csv_file:
         reader = csv.reader(csv_file);
         for line in reader:
             contacts.append(line[0]);
         csv_file.close();
     count = 1;
     for cont in contacts:
         print(count,".",cont);
         count +=1;


## delete contact from the list based on the phone number
def delete(phone):
      with open('contacts.csv','r') as input, open('contacts1.csv','a', newline='') as output:
          writer = csv.writer(output);
          contacts = [];
          for line in csv.reader(input):
              contacts.append(line);
          for cont in contacts:
              if cont[2] != phone:
               writer.writerow(cont);
      os.remove('contacts.csv');
      os.rename('contacts1.csv','contacts.csv');
      print("contact is deleted", phone);

## view contact details of the user.
def view(phone):
    data =[];
    count =0;
    with open('contacts.csv','r') as csv_file:
         reader = csv.reader(csv_file);
         for line in reader:
            count+=1;
            if line[2] == phone:
                data = line;
         csv_file.close();
    print("Number:", count);
    print("Name:", data[0]);
    print("Email:", data[1]);
    print("Phone:", data[2]);


##Contact Manager simulator. 
print("Contact Manager");
flag = 0;
while flag != 1:
    print("COMMAND MENU");
    print("list - Display all contacts");
    print("view - View a contact");
    print("add - Add a contact");
    print("del - Delete a contact");
    print("exit - Exit program");

    choice = input("Enter your choice:");
    if choice == 'list':
        list();
    else:
        if choice == 'add':
            name = input("Enter name:");
            email = input("Enter email: ");
            phone = input("Enter phone number: ");
            add(name,email,phone);
        else:
            if choice == 'view':
                phone = input("Enter phone number:");
                view(phone);
            else:
                if choice == 'del':
                    phone = input("Enter phone number:");
                    delete(phone);
                else:
                    if choice == 'exit':
                        flag = 1;

I tested and it run according to the requirements

Please please please upvote it will help me alot

Please dont downvote