🐍 کتابخانه مرجع پایتون

try:
    # کدی که ممکن است خطا دهد
    x = 10
    y = 0
    result = x / y
    print(f"Result: {result}")
except ZeroDivisionError:
    print("Error: Cannot divide by zero!")
except Exception as e:
    print(f"An unexpected error occurred: {e}")

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try:
    # کدی که ممکن است خطا دهد
    num = int(input("Enter a number: "))
except ValueError:
    print("Error: Invalid number!")
else:
    # این بخش فقط در صورت عدم وجود خطا اجرا می‌شود
    print(f"You entered: {num}")
    print(f"Square: {num ** 2}")

try:
    file = open("test.txt", "r")
    content = file.read()
    print(content)
except FileNotFoundError:
    print("Error: File not found!")
finally:
    print("This block always executes.")

def validate_age(age):
    if age < 0:
        raise ValueError("Age cannot be negative!")
    elif age > 150:
        raise ValueError("Age cannot be more than 150!")
    else:
        return f"Valid age: {age}"

try:
    print(validate_age(25))    # Valid
    print(validate_age(-5))    # Error
except ValueError as e:
    print(f"Error: {e}")

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# تعریف استثنای سفارشی
class InsufficientBalanceError(Exception):
    """Exception raised when account balance is insufficient."""
    def __init__(self, balance, amount):
        self.balance = balance
        self.amount = amount
        self.message = f"Cannot withdraw {amount}. Balance is {balance}."
        super().__init__(self.message)

class BankAccount:
    def __init__(self, balance):
        self.balance = balance

    def withdraw(self, amount):
        if amount > self.balance:
            raise InsufficientBalanceError(self.balance, amount)
        self.balance -= amount
        return f"Withdrew {amount}. New balance: {self.balance}"

# استفاده
account = BankAccount(100)
try:
    print(account.withdraw(50))   # OK
    print(account.withdraw(80))   # Error
except InsufficientBalanceError as e:
    print(f"Error: {e}")

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def divide(a, b):
    assert b != 0, "Divisor cannot be zero!"
    return a / b

try:
    print(divide(10, 2))  # 5.0
    print(divide(10, 0))  # AssertionError
except AssertionError as e:
    print(f"Assertion Error: {e}")

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import logging

# تنظیم logging
logging.basicConfig(
    level=logging.ERROR,
    format='%(asctime)s - %(levelname)s - %(message)s'
)

try:
    result = 10 / 0
except ZeroDivisionError as e:
    logging.error(f"Error occurred: {e}")
    print("Error logged. Check the log for details.")

# همچنین می‌توانید خطاهای سطح پایین‌تر را ثبت کنید
logging.warning("This is a warning message")
logging.info("This is an info message")

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import logging

# تنظیم logging
logging.basicConfig(level=logging.ERROR)

class UserNotFoundError(Exception):
    pass

class UserManager:
    def __init__(self):
        self.users = {}

    def add_user(self, username, age):
        if not username:
            raise ValueError("Username cannot be empty!")
        if age < 0:
            raise ValueError("Age cannot be negative!")
        if username in self.users:
            raise KeyError(f"Username '{username}' already exists!")
        self.users[username] = age
        logging.info(f"User {username} added successfully.")

    def get_user(self, username):
        if username not in self.users:
            raise UserNotFoundError(f"User '{username}' not found!")
        return self.users[username]

    def delete_user(self, username):
        if username not in self.users:
            raise UserNotFoundError(f"User '{username}' not found!")
        age = self.users.pop(username)
        logging.info(f"User {username} (age {age}) deleted.")
        return age

# استفاده
manager = UserManager()

try:
    manager.add_user("Saba", 25)
    manager.add_user("Ali", 30)
    manager.add_user("Saba", 28)  # Duplicate username
except ValueError as e:
    print(f"Error: {e}")
except KeyError as e:
    print(f"Error: {e}")

# دریافت کاربر
try:
    print(manager.get_user("Saba"))   # 25
    print(manager.get_user("Hossein")) # Not found
except UserNotFoundError as e:
    print(f"Error: {e}")

# نمایش لیست کاربران
print("\nAll users:")
for username, age in manager.users.items():
    print(f"{username}: {age} years old")

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