exceptions.py

class CustomError(Exception):
    def __init__(self, message, code=None):
        super().__init__(message)
        self.code = code

class NotFoundError(CustomError):
    def __init__(self, resource):
        super().__init__(f'{resource} not found', code=404)

class InvalidInputError(CustomError):
    def __init__(self, details):
        super().__init__(f'Invalid input: {details}', code=400)

class UnauthorizedAccessError(CustomError):
    def __init__(self):
        super().__init__('Unauthorized access', code=403)

# Example function demonstrating error handling

def fetch_resource(resource_id):
    resources = {1: 'Item 1', 2: 'Item 2'}
    if resource_id not in resources:
        raise NotFoundError(resource_id)
    return resources[resource_id]

try:
    print(fetch_resource(3))  
except CustomError as e:
    print(f'Error: {e}, Code: {e.code}')