Python CO – 4 Assignment Karann S
2210031
1. File Creation, Reading, Writing with Exception Handling & Menu-Based System
import os
def create_file():
filename = input("Enter filename: ")
content = input("Enter content for the file: ")
try:
with open(filename, "w") as file:
file.write(content)
print("File created successfully!")
except Exception as e:
print(f"Error: {e}")
def read_file():
filename = input("Enter filename to read: ")
try:
with open(filename, "r") as file:
print("File content:\n", file.read())
except FileNotFoundError:
print("Error: File not found.")
except PermissionError:
print("Error: Permission denied.")
except Exception as e:
print(f"Error: {e}")
def write_to_file():
filename = input("Enter filename to write to: ")
content = input("Enter content to append: ")
try:
with open(filename, "a") as file:
file.write("\n" + content)
print("Content written successfully!")
except Exception as e:
print(f"Error: {e}")
def main():
while True:
print("\nMenu:")
print("1. Create a File")
print("2. Read a File")
print("3. Write to a File")
print("4. Exit")
choice = input("Enter your choice: ")
if choice == "1":
create_file()
elif choice == "2":
read_file()
elif choice == "3":
write_to_file()
elif choice == "4":
print("Exiting...")
break
else:
print("Invalid choice! Try again.")
if __name__ == "__main__":
main()
2. String Formatting in Python:
# Using % Operator
name = "Alice"
age = 25
print("Hello, %s! You are %d years old." % (name, age))
# Using .format() Method
print("Hello, {}! You are {} years old.".format(name, age))
print("Hello, {1}! You are {0} years old.".format(age, name))
# Using f-strings
print(f"Hello, {name}! You are {age} years old.")
3.Student Management System Using Python Packages
student_management/
Project Structure:
│── __init__.py
│── student.py
│── database.py
│── main.py
(Student Class):
class Student:
def __init__(self, name, roll_no):
self.name = name
self.roll_no = roll_no
def __str__(self):
return f"Roll No: {self.roll_no}, Name: {self.name}"
(Handling Student Data):
import pickle
STUDENT_FILE = "students.dat"
def save_students(students):
with open(STUDENT_FILE, "wb") as file:
pickle.dump(students, file)
def load_students():
try:
with open(STUDENT_FILE, "rb") as file:
return pickle.load(file)
except FileNotFoundError:
return []
(Main Program):
from student_management.student import Student
from student_management.database import save_students, load_students
students = load_students()
def add_student():
name = input("Enter student name: ")
roll_no = input("Enter roll number: ")
students.append(Student(name, roll_no))
save_students(students)
print("Student added successfully!")
def display_students():
if not students:
print("No students found.")
else:
for student in students:
print(student)
def remove_student():
roll_no = input("Enter roll number to remove: ")
global students
students = [s for s in students if s.roll_no != roll_no]
save_students(students)
print("Student removed successfully!")
def main():
while True:
print("\nStudent Management System")
print("1. Add Student")
print("2. Display Students")
print("3. Remove Student")
print("4. Exit")
choice = input("Enter choice: ")
if choice == "1":
add_student()
elif choice == "2":
display_students()
elif choice == "3":
remove_student()
elif choice == "4":
print("Exiting...")
break
else:
print("Invalid choice!")
if __name__ == "__main__":
main()
4. Banking System Using Python Packages:
banking_system/
│── __init__.py
│── account.py
│── database.py
│── main.py
class Account:
def __init__(self, name, acc_no, balance=0):
self.name = name
self.acc_no = acc_no
self.balance = balance
def deposit(self, amount):
self.balance += amount
print(f"Deposited {amount}. New Balance: {self.balance}")
def withdraw(self, amount):
if amount > self.balance:
print("Insufficient balance!")
else:
self.balance -= amount
print(f"Withdrawn {amount}. New Balance: {self.balance}")
def __str__(self):
return f"Account No: {self.acc_no}, Name: {self.name}, Balance: {self.balance}"
import pickle
BANK_FILE = "accounts.dat"
def save_accounts(accounts):
with open(BANK_FILE, "wb") as file:
pickle.dump(accounts, file)
def load_accounts():
try:
with open(BANK_FILE, "rb") as file:
return pickle.load(file)
except FileNotFoundError:
return []
from banking_system.account import Account
from banking_system.database import save_accounts, load_accounts
accounts = load_accounts()
def create_account():
name = input("Enter account holder name: ")
acc_no = input("Enter account number: ")
accounts.append(Account(name, acc_no))
save_accounts(accounts)
print("Account created!")
def deposit_money():
acc_no = input("Enter account number: ")
amount = float(input("Enter amount to deposit: "))
for acc in accounts:
if acc.acc_no == acc_no:
acc.deposit(amount)
save_accounts(accounts)
return
print("Account not found!")
def withdraw_money():
acc_no = input("Enter account number: ")
amount = float(input("Enter amount to withdraw: "))
for acc in accounts:
if acc.acc_no == acc_no:
acc.withdraw(amount)
save_accounts(accounts)
return
print("Account not found!")
def display_accounts():
for acc in accounts:
print(acc)
def main():
while True:
print("\nBanking System")
print("1. Create Account")
print("2. Deposit Money")
print("3. Withdraw Money")
print("4. Display Accounts")
print("5. Exit")
choice = input("Enter choice: ")
if choice == "1":
create_account()
elif choice == "2":
deposit_money()
elif choice == "3":
withdraw_money()
elif choice == "4":
display_accounts()
elif choice == "5":
print("Exiting...")
break
else:
print("Invalid choice!")
if __name__ == "__main__":
main()
5. Library Management System Using Python Namespaces:
class Library:
def __init__(self):
self.books = []
def add_book(self, book):
self.books.append(book)
print("Book added successfully!")
def remove_book(self, book):
if book in self.books:
self.books.remove(book)
print("Book removed successfully!")
else:
print("Book not found!")
def search_book(self, book):
print("Book found!" if book in self.books else "Book not found!")
def display_books(self):
print("Available Books:", ", ".join(self.books) if self.books else "No books available.")
library = Library()
library.add_book("Python Basics")
library.display_books()
library.search_book("Python Basics")
library.remove_book("Python Basics")
library.display_books()
