Python · Quick Reference

Phase 3 Projects Cheat Sheet

Python

In one line: Classes, inheritance, file I/O, exceptions, and packages — all working together in 4 real, professional-grade programs. This is the finale.

Key Ideas

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Code Examples

import json
from abc import ABC, abstractmethod
from datetime import datetime

# ── Custom Exceptions ─────────────────────────
class BankError(Exception): pass
class InsufficientFunds(BankError):
    def __init__(self, need, have):
        super().__init__...

import csv
from datetime import date

class InventoryError(Exception): pass
class OutOfStockError(InventoryError):
    def __init__(self, name, want, have):
        super().__init__(f"{name}: need {want}, only {have} in stock")
class ExpiredProductError(Inv...

import random, json

class DeadCharacterError(Exception): pass

class Item:
    def __init__(self, name, effect, value):
        self.name  = name; self.effect = effect; self.value = value
    def use(self, char):
        if self.effect == "heal":
         ...