Generate a Python cheat sheet

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# Python Cheat Sheet 🐍

#############################
# BASIC SYNTAX & VARIABLES
#############################

# Comments
# This is a comment

# Variables
x = 5           # Integer
y = 3.14        # Float
name = "John"   # String
is_on = True    # Boolean

# Multiple assignment
a, b, c = 1, 2, 3

# Type checking
type(x)         # <class 'int'>

#############################
# DATA TYPES
#############################

# Strings
greet = "Hello"
greet[0]        # 'H'
greet.upper()   # 'HELLO'
greet.lower()   # 'hello'
greet.replace("l", "x")  # 'Hexxo'
"world" in greet  # False

# Numbers
2 + 3       # 5
2 ** 3      # 8 (exponent)
5 // 2      # 2 (floor division)
5 % 2       # 1 (modulus)

# Lists
my_list = [1, 2, 3]
my_list.append(4)
my_list[0]       # 1
my_list[-1]      # 4
my_list[1:3]     # [2, 3]

# Tuples (immutable)
my_tuple = (1, 2, 3)

# Sets
my_set = {1, 2, 2, 3}   # {1, 2, 3}
my_set.add(4)

# Dictionaries
person = {"name": "Alice", "age": 30}
person["name"]      # 'Alice'
person.get("age")   # 30
person["city"] = "NYC"

#############################
# CONTROL FLOW
#############################

# If statements
if x > 0:
    print("Positive")
elif x == 0:
    print("Zero")
else:
    print("Negative")

# For loop
for i in range(5):
    print(i)

# While loop
count = 0
while count < 5:
    print(count)
    count += 1

# Loop control
break       # exits the loop
continue    # skips to the next iteration

#############################
# FUNCTIONS
#############################

def greet(name):
    return f"Hello, {name}!"

def add(a, b=0):
    return a + b

# Lambda function
square = lambda x: x ** 2

#############################
# CLASSES & OBJECTS
#############################

class Dog:
    def __init__(self, name):
        self.name = name
    
    def speak(self):
        return f"{self.name} says woof!"

fido = Dog("Fido")
fido.speak()     # 'Fido says woof!'

#############################
# EXCEPTIONS
#############################

try:
    1 / 0
except ZeroDivisionError:
    print("Cannot divide by zero")
finally:
    print("Done")

#############################
# FILE I/O
#############################

# Write to file
with open("file.txt", "w") as f:
    f.write("Hello World")

# Read from file
with open("file.txt", "r") as f:
    content = f.read()

#############################
# COMMON MODULES
#############################

import math
math.sqrt(16)       # 4.0

import random
random.randint(1, 10)

from datetime import datetime
now = datetime.now()

import os
os.getcwd()         # Get current directory

#############################
# COMPREHENSIONS
#############################

# List comprehension
squares = [x**2 for x in range(10)]

# Dictionary comprehension
nums = {x: x*x for x in range(5)}

# Set comprehension
unique = {char for char in "hello"}

#############################
# ADVANCED TOPICS (BASICS)
#############################

# Generators
def gen():
    for i in range(3):
        yield i

# Decorators
def decorator(func):
    def wrapper():
        print("Before")
        func()
        print("After")
    return wrapper

@decorator
def say_hello():
    print("Hello")

# Context Managers
with open("file.txt") as f:
    data = f.read()

# Type hints
def add(a: int, b: int) -> int:
    return a + b