Python Programming Language Cheatsheet

Explore this comprehensive Python cheatsheet covering essential syntax, data structures, file handling, and object-oriented programming. Learn the fundamentals of Python programming with examples and quick references for both beginners and experienced developers.

Basics

Comments

# This is a single-line comment

"""
This is a
multi-line comment
"""

Variables

variable_name = 10
string_variable = "Hello, World!"

Data Types

int_num = 42
float_num = 3.14
string = "text"
boolean = True

Basic Input/Output

user_input = input("Enter something: ")
print("Output:", user_input)

String Manipulation

s1 = "Hello"
s2 = "World"
concatenated_string = s1 + " " + s2
formatted_string = f"{s1} {s2}"

Lists

my_list = [1, 2, 3, "four", 5.0]

Tuples

my_tuple = (1, 2, 3)

Dictionaries

my_dict = {"key": "value", "num": 42}

Conditions

if condition:
    # code
elif another_condition:
    # code
else:
    # code

Loops

for item in my_list:
    # code

while condition:
    # code

Functions

def my_function(param1, param2):
    # code
    return result

Advanced Data Structures

Sets

my_set = {1, 2, 3, 4}

List Comprehension

squared_numbers = [x**2 for x in range(1, 6)]

Dictionary Comprehension

my_dict = {key: value for key, value in zip(keys, values)}

Lambda Functions

square = lambda x: x**2

Map and Filter

squared_numbers = list(map(lambda x: x**2, my_list))
filtered_numbers = list(filter(lambda x: x > 0, my_list))

File Handling

Reading from a File

with open("filename.txt", "r") as file:
    content = file.read()

Writing to a File

with open("filename.txt", "w") as file:
    file.write("Hello, File!")

Exception Handling

try:
    # code
except ExceptionType as e:
    # handle exception

Modules and Packages

import module_name
from module_name import function_name

Object-Oriented Programming (OOP)

Class Definition

class MyClass:
    def __init__(self, param1, param2):
        self.param1 = param1
        self.param2 = param2

    def my_method(self):
        # code

Object Instantiation

obj = MyClass(arg1, arg2)
obj.my_method()

External Libraries (Example – NumPy)

Installing External Libraries

# Installing External Libraries
# pip install numpy

Using NumPy

# Using NumPy
import numpy as np

# NumPy Arrays
my_array = np.array([1, 2, 3, 4])
array_sum = np.sum(my_array)

Refer to the official documentation for more in-depth information and examples.

FAQ