Question

Re-write this Python code that counts down from 5 to 0 in a more efficient way:

import time
seconds = 5
print("Remaining time: " + str(seconds))
seconds = seconds - 1
time.sleep(1)
print("Remaining time: " + str(seconds))
seconds = seconds - 1
time.sleep(1)
print("Remaining time: " + str(seconds))
seconds = seconds - 1
time.sleep(1)
print("Remaining time: " + str(seconds))
seconds = seconds - 1
time.sleep(1)
print("Remaining time: " + str(seconds))
seconds = seconds - 1
time.sleep(1)
print("Remaining time: " + str(seconds))

Imagine you are writing a program that will be used to manage production at a cookie factory. Describe one object you will create; it should have at least two methods and three attributes.
Look at the following program. Is it procedural or object-oriented? What would you do to convert it to the other type?

song1 = "Let's Dance"
song1_info = [128, 34, 304]

song2 = "Party Time!"
song2_info = [144, 32, 439]

song3 = "My Dreams"
song3_info = [93, 41, 339]

Describe in your own words what this program does:

class Meals:
def __init__(self, name):
self.name = name

fish = Meals("salmon")
print(fish.name)

Write a Python module that solves a problem.

Answer 1

### 1. Efficient Countdown Code

Here’s a more efficient way to count down from 5 to 0 using a loop:

```python
import time

for seconds in range(5, -1, -1):
print(f"Remaining time: {seconds}")
time.sleep(1)
```

### 2. Object for Cookie Factory Management

In a cookie factory program, you might create a `CookieBatch` object with the following attributes and methods:

#### Attributes:
1. `batch_id`: A unique identifier for each batch of cookies.
2. `cookie_type`: The type of cookie being produced (e.g., chocolate chip, oatmeal raisin).
3. `quantity`: The number of cookies in the batch.

#### Methods:
1. `bake(batch_time)`: Simulates the baking process for a specified amount of time.
2. `report_status()`: Provides a summary of the batch, including batch ID, cookie type, and quantity.

### 3. Program Type Analysis

The given program is procedural because it operates on individual song variables and lists with no encapsulation or use of objects. To convert it to object-oriented programming, you could create a `Song` class to encapsulate the attributes and methods related to a song.

Here's an example of what that might look like:

```python
class Song:
def __init__(self, title, bpm, duration, file_size):
self.title = title
self.bpm = bpm
self.duration = duration
self.file_size = file_size

def play(self):
print(f"Playing '{self.title}' at {self.bpm} BPM.")

# Create song objects
song1 = Song("Let's Dance", 128, 34, 304)
song2 = Song("Party Time!", 144, 32, 439)
song3 = Song("My Dreams", 93, 41, 339)

# Example usage
song1.play()
```

### 4. Explanation of the Code

The class `Meals` is a simple example of object-oriented programming. When an object of the `Meals` class is instantiated, it initializes with a name for the meal. In the provided code, the `fish` object represents a meal called "salmon", and its name is then printed. Essentially, this program creates a meal instance and outputs its name.

### 5. Python Module to Solve a Problem

Here's a Python module that could solve a basic arithmetic problem by providing a simple calculator functionality:

```python
# calculator.py

class Calculator:
def add(self, a, b):
return a + b

def subtract(self, a, b):
return a - b

def multiply(self, a, b):
return a * b

def divide(self, a, b):
if b == 0:
raise ValueError("Cannot divide by zero.")
return a / b

if __name__ == "__main__":
calc = Calculator()
print("Add 5 + 3 =", calc.add(5, 3))
print("Subtract 5 - 3 =", calc.subtract(5, 3))
print("Multiply 5 * 3 =", calc.multiply(5, 3))
print("Divide 5 / 3 =", calc.divide(5, 3))
```

This `calculator.py` module defines a `Calculator` class with methods to perform basic arithmetic operations. The `if __name__ == "__main__":` block allows for basic testing of the functionality when the module is run as a standalone script.