Most Popular Built-in Methods in Python

Python, a versatile and powerful programming language, comes equipped with a multitude of built-in methods that simplify various tasks. These methods are like tools in a developer's toolkit, offering efficient solutions for everyday programming challenges. In this guide, we'll delve into some of the most frequently used built-in methods across different data types and scenarios. With explanations and practical examples, you'll gain a solid understanding of how to leverage these methods to enhance your Python coding skills.


List Methods: Manipulating Sequences of Elements

Lists are fundamental data structures in Python, and they offer several built-in methods to manipulate their contents.



The append() method adds an element to the end of a list.

fruits = ['apple', 'banana', 'cherry']


print(fruits)  # Output: ['apple', 'banana', 'cherry', 'orange']



The insert() method inserts an element at a specified position within the list.

numbers = [1, 2, 3, 5]

numbers.insert(3, 4)

print(numbers)  # Output: [1, 2, 3, 4, 5]



The pop() method removes and returns an element from a specific position in the list.

colors = ['red', 'green', 'blue']

removed_color = colors.pop(1)

print(colors)  # Output: ['red', 'blue']

print(removed_color)  # Output: 'green'



The sort() method arranges the elements of a list in ascending order.

numbers = [3, 1, 4, 1, 5, 9, 2, 6]


print(numbers)  # Output: [1, 1, 2, 3, 4, 5, 6, 9]



The reverse() method reverses the order of elements in the list.

letters = ['a', 'b', 'c', 'd']


print(letters)  # Output: ['d', 'c', 'b', 'a']



The sum() function calculates the sum of all elements in an iterable.

numbers = [1, 2, 3, 4, 5]

total = sum(numbers)

print(total)  # Output: 15



The len() function returns the number of elements in an iterable.

fruits = ['apple', 'banana', 'cherry']

num_fruits = len(fruits)

print(num_fruits)  # Output: 3



Numeric Functions: Working with Numbers

Python offers several built-in functions for numeric operations.



The abs() function returns the absolute value of a number.

num = -5

abs_num = abs(num)

print(abs_num)  # Output: 5



The round() function rounds a floating-point number to a specified number of decimal places.

pi = 3.14159

rounded_pi = round(pi, 2)

print(rounded_pi)  # Output: 3.14


min() and max()

The min() and max() functions return the smallest and largest values from an iterable, respectively.

numbers = [7, 3, 9, 2, 5]

min_number = min(numbers)

max_number = max(numbers)

print(min_number)  # Output: 2

print(max_number)  # Output: 9


String Methods

Strings are a cornerstone of programming, and Python offers various built-in methods to manipulate and analyze text data.


upper() and lower()

The upper() and lower() methods convert strings to uppercase and lowercase, respectively.

text = "Hello, World!"

uppercase_text = text.upper()

lowercase_text = text.lower()

print(uppercase_text)  # Output: "HELLO, WORLD!"

print(lowercase_text)  # Output: "hello, world!"



The strip() method removes leading and trailing whitespace from a string.

message = "   Welcome!   "

cleaned_message = message.strip()

print(cleaned_message)  # Output: "Welcome!"



The replace() method substitutes a substring with another substring.

sentence = "I like cats."

new_sentence = sentence.replace("cats", "dogs")

print(new_sentence)  # Output: "I like dogs."



The split() method splits a string into a list of substrings using a specified delimiter.

sentence = "Python is fun!"

words = sentence.split()

print(words)  # Output: ['Python', 'is', 'fun!']



Dictionary Methods: Managing Key-Value Pairs

Dictionaries offer efficient ways to store and manage key-value pairs. Python provides essential methods for dictionary manipulation.


keys(), values(), and items()

These methods retrieve the keys, values, and key-value pairs from a dictionary.

person = {'name': 'Alice', 'age': 30, 'city': 'New York'}

keys = person.keys()

values = person.values()

items = person.items()

print(keys)  # Output: dict_keys(['name', 'age', 'city'])

print(values)  # Output: dict_values(['Alice', 30, 'New York'])

print(items)  # Output: dict_items([('name', 'Alice'), ('age', 30), ('city', 'New York')])



The get() method retrieves a value from a dictionary based on a key.

population = {'USA': 331002651, 'China': 1439323776}

usa_population = population.get('USA')

print(usa_population)  # Output: 331002651



By mastering these methods, you'll significantly enhance your ability to manipulate lists, strings, and dictionaries efficiently.

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Read More....
Arrays and Lists in Python
Python Iterators
Lambda or Anonymous Functions in Python
Python Decorators
Python Dictionaries