❔ Interview question

What is the output of the following code?

def outer():
    x = 10
    def inner():
        nonlocal x
        x += 5
        return x
    return inner()

result = outer()
print(result)

Answer:
15

tags: #python #advanced #coding #programming #interview #nonlocal #function #dev

By: t.iss.one/DataScienceQ 🚀

⁉️ Interview question

What is the output of the following code?

import copy

a = [1, 2, [3, 4]]
b = copy.deepcopy(a)
b[2][0] = 'X'
print(a[2][0])

Answer:
3

#⃣ tags: #python #advanced #coding #programming #interview #deepcopy #mutable #dev

By: t.iss.one/DataScienceQ 🚀

⁉️ Interview question

What is the output of the following code?

def func(a, b=[]):
    b.append(a)
    return b

print(func(1))
print(func(2))

Answer:
[1, 2]

#⃣ tags: #python #advanced #coding #programming #interview #defaultarguments #mutable #dev

By: t.iss.one/DataScienceQ 🚀

⁉️ Interview question

What is the output of the following code?

class A:
    def __init__(self):
        self.x = 1

    def __str__(self):
        return str(self.x)

a = A()
print(a)

Answer:
1

#️⃣ tags: #python #advanced #coding #programming #interview #strmethod #object #dev

By: t.iss.one/DataScienceQ 🚀

1. What is a database?
2. Why do we use databases in Python?
3. Name a popular database library for Python.
4. How do you connect to a SQLite database in Python?
5. What is the purpose of cursor() in database operations?
6. How do you execute a query in Python using SQLite?

---

Explanation with Code Example (Beginner Level):

import sqlite3

# 1. Create a connection to a database (or create it if not exists)
conn = sqlite3.connect('example.db')

# 2. Create a cursor object to interact with the database
cursor = conn.cursor()

# 3. Create a table
cursor.execute('''
    CREATE TABLE IF NOT EXISTS users (
        id INTEGER PRIMARY KEY,
        name TEXT NOT NULL,
        age INTEGER
    )
''')

# 4. Insert data into the table
cursor.execute("INSERT INTO users (name, age) VALUES ('Alice', 25)")
cursor.execute("INSERT INTO users (name, age) VALUES ('Bob', 30)")

# 5. Commit changes
conn.commit()

# 6. Query the data
cursor.execute("SELECT * FROM users")
rows = cursor.fetchall()
for row in rows:
    print(row)

# Close connection
conn.close()

This example shows how to:
- Connect to a SQLite database.
- Create a table.
- Insert and retrieve data.

Answer:
1. A database is an organized collection of data.
2. We use databases to store, manage, and retrieve data efficiently.
3. sqlite3 is a popular library.
4. Use sqlite3.connect() to connect.
5. cursor() allows executing SQL commands.
6. Use cursor.execute() to run queries.

#Python #Databases #SQLite #Beginner #Programming #Coding #LearnToCode

By: @DataScienceQ 🚀

1. What is a GUI?
2. Why use GUI in Python?
3. Name a popular GUI library for Python.
4. How do you create a window using Tkinter?
5. What is the purpose of mainloop() in Tkinter?
6. How do you add a button to a Tkinter window?

---

Explanation with Code Example (Beginner Level):

import tkinter as tk

# 1. Create the main window
root = tk.Tk()
root.title("My First GUI")

# 2. Add a label
label = tk.Label(root, text="Hello, World!")
label.pack()

# 3. Add a button
def on_click():
    print("Button clicked!")

button = tk.Button(root, text="Click Me", command=on_click)
button.pack()

# 4. Run the application
root.mainloop()

This code creates a simple GUI window with a label and button.

Answer:
1. GUI stands for Graphical User Interface.
2. To create interactive applications with buttons, forms, etc.
3. Tkinter is a popular library.
4. Use tk.Tk() to create a window.
5. mainloop() keeps the window open and responsive.
6. Use tk.Button() and .pack() to add a button.

#Python #GUI #Tkinter #Beginner #Programming #Coding #LearnToCode

By: @DataScienceQ 🚀

Python Tip: Tuple Unpacking for Multiple Assignments

Assigning multiple variables at once from a sequence can be done elegantly using tuple unpacking (also known as sequence unpacking). It's clean and efficient.

Traditional way:

coordinates = (10, 20)
x = coordinates[0]
y = coordinates[1]
print(f"X: {x}, Y: {y}")

Using Tuple Unpacking:

coordinates = (10, 20)
x, y = coordinates
print(f"X: {x}, Y: {y}")

This also works with lists and functions that return multiple values. It's often used for swapping variables without a temporary variable:

a = 5
b = 10
a, b = b, a # Swaps values of a and b
print(f"a: {a}, b: {b}") # Output: a: 10, b: 5

#PythonTip #TupleUnpacking #Assignment #Pythonic #Coding
---
By: @DataScienceQ ✨