
A complete set of Python code snippets that you can implement in your projects. Best for beginners who want to improve their Python programming skills.
What is Python?
Python is a general-purpose, high-level programming language with simple, easy-to-read syntax. It's extensively used in web development, data science, automation, and so much more, making it an ideal language for beginners to learn how to code.
It's gained popularity in recent years due to its simplicity and readability, which makes it an ideal choice for beginners.
Table of Contents
- Hello, World!
- Swap Two Variables
- Reverse a String
- Check if a String is a Palindrome
- Mastering List Comprehension
- Remove Duplicates from a List
- Find the Most Frequent Element
- Flatten a Nested List
- How to Read a File
- How to Write to a File
- Merge Two Dictionaries
- Check if a File Exists
- Get the Current Date and Time
- Generate a Random Number
- Convert String to Title Case
- The Ternary Conditional Operator
- Effortless String Formatting with f-Strings
- Measure Your Code's Execution Time
- Creating a Simple Function
- Check for Anagrams
1. Hello, World!
The classic first step for any aspiring programmer. This simple line of code is a great way to make sure your Python environment is up and running.
print("Hello, World!")
For more details on the print
function, see the official Python documentation.
2. Swap Two Variables
Here's how you can easily swap the values of two variables using a simple assignment statement.
a, b = 5, 10
a, b = b, a
print(f"a = {a}, b = {b}") # Result: a = 10, b = 5
3. Reverse a String
Need to flip a string? Python's slicing feature makes it incredibly simple. Here's how you can do it in just one line.
my_string = "CodeShack"
reversed_string = my_string[::-1]
print(reversed_string) # Result: "ckahSedoc"
4. Check if a String is a Palindrome
Palindromes are words that basically read the same forward and backward. This snippet combines our string reversal trick with a simple comparison to easily check for palindromes.
my_string = "racecar"
is_palindrome = my_string == my_string[::-1]
print(is_palindrome) # Result: True
my_string = "hello"
is_palindrome = my_string == my_string[::-1]
print(is_palindrome) # Result: False
5. Mastering List Comprehension
List comprehensions offer a more concise and readable way to create lists. This example finds all words longer than five characters from a list and adds them to a new list in uppercase.
words = ["apple", "banana", "cherry", "date", "elderberry"]
long_words_upper = [word.upper() for word in words if len(word) > 5]
print(long_words_upper) # Result: ['BANANA', 'CHERRY', 'ELDERBERRY']
Learn more about the power of list comprehensions in the official tutorial.
6. Remove Duplicates from a List
This snippet provides a quick and easy way to remove duplicate items from a list by utilizing the properties of a set.
my_list = [7, 7, 1, 2, 3, 4, 4, 4, 5, 5]
my_unique_list = list(set(my_list))
print(my_unique_list) # Result: [7, 1, 2, 3, 4, 5]
Pretty cool, right? Let's move on...
7. Find the Most Frequent Element
Here's a clever one-liner to find the most common element in a list.
my_list = [1, 1, 2, 3, 4, 5, 5, 5, 6, 6]
most_frequent = max(set(my_list), key=my_list.count)
print(most_frequent) # Result: 5
8. Flatten a Nested List
The following snippet will convert a nested list (or multidimensional list) into a single, flat list.
nested_list = [[1, 2, 3], [4], [5], [6, 7], [8, 9]]
flat_list = [item for sublist in nested_list for item in sublist]
print(flat_list) # Result: [1, 2, 3, 4, 5, 6, 7, 8, 9]
9. How to Read a File
The with
statement is the ideal way to handle files in Python, as it ensures they are automatically closed. Here's how to read the contents of a text file.
with open('my_file.txt', 'r') as f:
content = f.read()
print(content)
10. How to Write to a File
The below snippet will write text to a text file and create the file if it doesn't already exist. If the file exists, it will overwrite its contents.
with open('my_file.txt', 'w') as f:
f.write('Hello from Python!')
11. Merge Two Dictionaries
This snippet demonstrates a clean way to easily merge two dictionaries into one.
dict1 = {'a': 1, 'b': 2}
dict2 = {'c': 3, 'd': 4}
merged_dict = {**dict1, **dict2}
print(merged_dict) # Result: {'a': 1, 'b': 2, 'c': 3, 'd': 4}
12. Check if a File Exists
Before you try to read from a file, it's wise to check if it actually exists. The os
module makes this so easy.
import os
if os.path.exists('my_file.txt'):
print("File exists")
else:
print("File does not exist")
Explore more file and directory operations in the os.path
documentation.
13. Get the Current Date and Time
The datetime
module is your go-to for working with dates and times in Python.
from datetime import datetime
now = datetime.now()
print(now.strftime("%Y-%m-%d %H:%M:%S"))
For more information on date and time formatting, check out the datetime
documentation.
14. Generate a Random Number
The random
module lets you generate random numbers. Here's how to get a random integer within a specific range.
import random
random_number = random.randint(1, 100)
print(random_number)
Discover more about generating random data in the random
module documentation.
15. Convert String to Title Case
This snippet will capitalize the first letter of each word in a string.
my_string = "hello world"
title_case_string = my_string.title()
print(title_case_string) # Result: Hello World
16. The Ternary Conditional Operator
A ternary operator is a clean, one-line alternative to a simple if/else statement.
age = 32
status = "Adult" if age >= 18 else "Minor"
print(status) # Result: Adult
17. Effortless String Formatting with f-Strings
F-strings offer a simple and intuitive way to embed expressions within your strings.
name = "Alice"
age = 30
print(f"{name} is {age} years old.") # Result: Alice is 30 years old.
You can learn more about f-strings in the official Python documentation.
18. Measure Your Code's Execution Time
Curious about how long your script takes to run? The time
module can help you find out.
import time
start_time = time.time()
# Your code here
time.sleep(1) # Simulating a 1-second task
end_time = time.time()
print(f"Execution time: {end_time - start_time:.4f} seconds")
For more timing functions, refer to the time
module documentation.
19. Creating a Simple Function
This snippet shows the basic structure of defining and calling a function that takes an argument.
def greet(name):
return f"Hello, {name}!"
print(greet("Bob")) # Result: Hello, Bob!
20. Check for Anagrams
Anagrams are words that basically have the same letters but in a different order. The Counter
class from the collections
module is perfect for this.
from collections import Counter
str1 = "listen"
str2 = "silent"
print(Counter(str1) == Counter(str2)) # Result: True
See what else you can do with the Counter
object.
Frequently Asked Questions (FAQ)
Why are these Python snippets so useful?
These snippets tackle common, everyday programming challenges. Mastering them will help you build a strong foundation for tackling more complex projects and writing cleaner, more efficient code.
How can I run this code?
You can run this code in any standard Python environment. This includes your local command line, an Integrated Development Environment (IDE) like VS Code or PyCharm, or an online platform such as Replit.
Can I build a complete application with just these snippets?
Not by themselves. Think of these snippets as individual building blocks. A full-fledged application requires you to combine these and many other components with your own logic to create something bigger.
Final Thoughts
That's it for our collection of must-know Python snippets! Have these at your fingertips, whether you're a new coder or just happen to find yourself needing a quick reminder.
Got a favorite snippet of your own? Share it in the comments below!
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Happy coding!