final_assessment.py

# ==========================================
# Python Learning Lab: Final Assessment
# ==========================================
# Solve the five core challenges below to complete the course!
# Run: `python final_assessment.py` to check your work.

import os
import json

print("--- Running Final Assessment ---")

# ==========================================
# Challenge 1: Memoized Fibonacci
# ==========================================
# Write a recursive function `fibonacci(n)` that returns the n-th Fibonacci number.
# Implement a basic dictionary memoization (`memo = {}`) to optimize execution speed.
# Fibonacci Sequence: 0, 1, 1, 2, 3, 5, 8, 13, 21, 34...

memo = {}

def fibonacci(n):
    # TODO: Implement memoized fibonacci
    if n in memo:
        return memo[n]
    if n == 0:
        return 0
    if n == 1:
        return 1
    memo[n] = fibonacci(n - 1) + fibonacci(n - 2)
    return memo[n]

# --- Verification ---
assert fibonacci(0) == 0, "Fib(0) should be 0"
assert fibonacci(1) == 1, "Fib(1) should be 1"
assert fibonacci(10) == 55, "Fib(10) should be 55"
assert fibonacci(50) == 12586269025, "Memoization is required or n=50 will hang!"
print("✓ Challenge 1 passed!")


# ==========================================
# Challenge 2: Anagram Detector
# ==========================================
# Write a function `is_anagram(str1, str2)` that returns True if two strings are
# anagrams of each other (case-insensitive, ignoring spaces).
# An anagram is a word formed by rearranging the letters of another (e.g. "Listen", "Silent").

def is_anagram(str1, str2):
    # TODO: Clean strings and determine if they are anagrams
    clean1 = sorted(str1.lower().replace(" ", ""))
    clean2 = sorted(str2.lower().replace(" ", ""))
    return clean1 == clean2

# --- Verification ---
assert is_anagram("Listen", "Silent") is True, "Listen and Silent are anagrams"
assert is_anagram("Astronomer", "Moon starer") is True, "Spaces and case should be ignored"
assert is_anagram("hello", "bello") is False, "Not anagrams"
print("✓ Challenge 2 passed!")


# ==========================================
# Challenge 3: Word Count Analytics
# ==========================================
# Write a function `word_frequencies(paragraph)` that:
# 1. Splits text by space and strips punctuation marks (comma, period, exclamation).
# 2. Converts words to lowercase.
# 3. Returns a dictionary containing word-to-count mapping.

def word_frequencies(paragraph):
    # TODO: Perform text processing and count word occurrences
    import string
    words = paragraph.lower().split()
    counts = {}
    for w in words:
        cleaned = w.strip(string.punctuation)
        if cleaned:
            counts[cleaned] = counts.get(cleaned, 0) + 1
    return counts

# --- Verification ---
text = "Python is great. Learning Python is fun! Programming is also great."
counts = word_frequencies(text)
assert counts["python"] == 2, f"Expected 2 pythons, got {counts.get('python')}"
assert counts["is"] == 3, f"Expected 3 'is', got {counts.get('is')}"
assert counts["fun"] == 1, f"Expected 1 'fun', got {counts.get('fun')}"
print("✓ Challenge 3 passed!")


# ==========================================
# Challenge 4: Custom Abstract Class Structure
# ==========================================
# 1. Define an abstract class `Shape` with an abstract method `area()`.
# 2. Create `Circle` subclass initializing with `radius`.
# 3. Create `Rectangle` subclass initializing with `width` and `height`.
# 4. Use `3.14159` as value for pi.

from abc import ABC, abstractmethod

class Shape(ABC):
    @abstractmethod
    def area(self):
        pass

class Circle(Shape):
    def __init__(self, radius):
        # TODO: Set radius
        self.radius = radius

    def area(self):
        # TODO: Return area of circle
        return 3.14159 * (self.radius ** 2)

class Rectangle(Shape):
    def __init__(self, width, height):
        # TODO: Set width and height
        self.width = width
        self.height = height

    def area(self):
        # TODO: Return area of rectangle
        return float(self.width * self.height)

# --- Verification ---
circle = Circle(5)
rectangle = Rectangle(4, 6)

assert abs(circle.area() - 78.53975) < 1e-4, f"Circle area incorrect: {circle.area()}"
assert rectangle.area() == 24.0, f"Rectangle area incorrect: {rectangle.area()}"
print("✓ Challenge 4 passed!")


# ==========================================
# Challenge 5: Log Parser Pipeline
# ==========================================
# Complete `parse_and_export_logs(log_data, output_filepath)`:
# 1. Parse lines of text where format is: "[LEVEL] MESSAGE" (e.g. "[ERROR] Connection failed")
# 2. Filter for logs containing '[ERROR]'.
# 3. Write those error messages as a list of strings into a JSON file at `output_filepath`.

def parse_and_export_logs(log_lines, output_filepath):
    # TODO: Parse lines, filter errors, and write to JSON
    errors = []
    for line in log_lines:
        if line.startswith("[ERROR]"):
            msg = line.replace("[ERROR] ", "", 1)
            errors.append(msg)
    with open(output_filepath, "w") as f:
        json.dump(errors, f)

# --- Verification ---
logs = [
    "[INFO] System started",
    "[ERROR] Database unreachable",
    "[WARN] High memory usage detected",
    "[ERROR] Disk sector corrupt"
]
out_path = "errors.json"
parse_and_export_logs(logs, out_path)

assert os.path.exists(out_path), "JSON output file was not generated"
with open(out_path, "r") as f:
    errors = json.load(f)
assert len(errors) == 2, f"Expected 2 error logs, got {len(errors)}"
assert "Database unreachable" in errors, "Could not find expected error message"

# Cleanup
if os.path.exists(out_path):
    os.remove(out_path)
print("✓ Challenge 5 passed!")

print("\n🎉 Congratulations! You have passed the Python Final Assessment!")