Insect Data Persistence - Python Programming Exercise

import pickle

class Insect:
    """Represents an insect with a name and number of legs."""

    def __init__(self, name, legs):
        """Initialize the insect with a name and number of legs."""
        self.name = name
        self.legs = legs

    def show_data(self):
        """Display the insect's data."""
        print(f"Name: {self.name}, Legs: {self.legs}")


class InsectManager:
    """Manages a collection of insects and handles persistence."""

    def __init__(self, filename):
        """Initialize the manager with a file for persistence."""
        self.filename = filename
        self.insects = []

    def add_insect(self, insect):
        """Add a new insect to the collection."""
        self.insects.append(insect)

    def show_all_insects(self):
        """Display all insects in the collection."""
        if not self.insects:
            print("No insects available.")
        else:
            for i, insect in enumerate(self.insects, start=1):
                print(f"Insect {i}:")
                insect.show_data()

    def save_to_file(self):
        """Persist the collection of insects to a file."""
        try:
            with open(self.filename, 'wb') as file:
                pickle.dump(self.insects, file)
            print(f"Data successfully saved to {self.filename}.")
        except Exception as e:
            print(f"Error while saving data: {e}")

    def load_from_file(self):
        """Load the collection of insects from a file."""
        try:
            with open(self.filename, 'rb') as file:
                self.insects = pickle.load(file)
            print(f"Data successfully loaded from {self.filename}.")
        except FileNotFoundError:
            print(f"No data file found. Starting with an empty collection.")
        except Exception as e:
            print(f"Error while loading data: {e}")


# Test Program
if __name__ == "__main__":
    # File to persist insect data
    data_file = "insects_data.bin"

    # Create an instance of the InsectManager
    manager = InsectManager(data_file)

    # Load existing data from the file
    print("Loading data from file...")
    manager.load_from_file()

    # Add new insects
    print("\nAdding new insects...")
    manager.add_insect(Insect("Ant", 6))
    manager.add_insect(Insect("Spider", 8))
    manager.add_insect(Insect("Centipede", 100))

    # Display all insects
    print("\nCurrent insects in collection:")
    manager.show_all_insects()

    # Save data to the file
    print("\nSaving data to file...")
    manager.save_to_file()

    # Clear the current collection
    print("\nClearing current collection...")
    manager.insects = []

    # Display after clearing
    print("\nInsects after clearing:")
    manager.show_all_insects()

    # Reload data from the file
    print("\nReloading data from file...")
    manager.load_from_file()

    # Display reloaded data
    print("\nInsects after reloading:")
    manager.show_all_insects()

 Output

Saving data to file...

Clearing current collection...

Insects after clearing:
No insects available.

Reloading data from file...

Insects after reloading:
Insect 1:
Name: Ant, Legs: 6
Insect 2:
Name: Spider, Legs: 8
Insect 3:
Name: Centipede, Legs: 100