Python Built-in Functions

The Python built-in functions are defined as the functions whose functionality is pre-defined in Python. In this article, I have explained a list of all functions of Python with examples.

In order to use these functions you don't have to install and import any module, These functions by default come with the python installation and are available to use directly.

List of Python Built-in Functions

The following are the most used built-in functions in Python. I have converted pretty much all functions and explained each one with examples below.

| Function | Built-in Function Description | | --- | --- | | abs() | The abs() function in Python returns the absolute value of a number | | all() | Return true if all items in an iterable (e.g. list, tuple, set, etc.) are True else it returns False | | any() | Returns true if any item in an iterable( list, dictionary, tuple, set, etc) is True else it returns False | | ascii() | Returns a string containing a printable representation of an object. It is similar to the repr() function. | | bin() | Returns a string representation of the binary value of a non-negative integer. | | bool() | Returns or convert the Boolean value of a specified object. i.e., True or False | | bytearray() | It returns a bytearray object which is an array of given bytes | | bytes() | Convert an object to an immutable byte-represented object of a given size and data. | | callable() | Returns True if the object passed appears to be callable, otherwise False | | chr() | The chr() function in Python is used to return a string representing a character whose Unicode code point is an integer. | | classmethod() | The classmethod() decorator in Python is used to define a method that is bound to the class and not the instance of the object. | | compile() | The compile() function in Python is used to convert a source code string into a code object that can be executed by the Python interpreter. | | complex() | The complex() function in Python is used to create a complex number. | | delattr() | The delattr() function in Python is used to delete an attribute from an object | | dict() | The dict() function in Python is used to create a new dictionary. | | dir() | The dir() function in Python is used to find out all the attributes and methods of an object, including the ones that are inherited from its parent classes. | | divmod() | The divmod() function in Python takes two arguments, a numerator, and a denominator, and returns a tuple containing the quotient and remainder of their division | | enumerate() | It adds a counter to an iterable and returns it as an enumerate object | | eval() | Evaluates a string as a Python and executes an expression and returns the result | | exec() | Execute a string containing a Python script and specified code (or object) | | filter() | Use a filter function to exclude items in an iterable object | | float() | Converts a number or a string to a floating-point number | | format() | Formats a specified value | | frozenset() | Creates an immutable frozenset object | | getattr() | Returns the value of a named attribute of an object | | globals() | Returns a dictionary of the current global symbol table | | hasattr() | Returns True if the object has an attribute with the given name, and False otherwise | | hash() | Returns the hash value of an object | | help() | Displays the documentation of the specified object or modules, functions, classes, keywords, etc | | hex() | Converts an integer to a hexadecimal string | | id() | Return the identity of an object | | input() | Allowing user input | | int() | converts a number or a string to an integer | | isinstance() | Returns True if a specified object is an instance of a specified object | | issubclass() | Returns True if the class is a subclass (direct, indirect, or virtual) of the class info, otherwise False | | iter() | Returns an iterator object | | len() | Returns the length of the object | | list() | Returns a list in Python | | locals() | Returns an updated dictionary of the current local symbol table | | map() | Applies a specified function to each item of an iterable and returns an iterator of the results. | | max() | It returns the largest item in an iterable | | memoryview() | Returns a memory view object | | min() | It returns the smallest item in an iterable or the smallest of two or more arguments | | next() | It returns the next item in an iterable | | object() | It returns a new object | | oct() | Converts a number into an octal | | open() | It opens a file and returns its object | | ord() | Convert an integer representing the Unicode equivalence of the passed argument | | pow() | Calculate the power of a number | | print() | Prints to the standard output device | | property() | Create a property of a class | | range() | Returns a sequence of numbers | | repr() | Returns a readable version of an object | | reversed() | Returns an iterator that accesses the given sequence in the reverse order | | round() | Rounds the number of digits and returns the floating-point number | | set() | Convert any of the iterable to the sequence of iterable elements with distinct elements. Returns a new set object | | setattr() | Sets an attribute (property/method) of an object | | slice() | Returns a slice object | | sorted() | Returns a sorted list | | staticmethod() | Converts a method into a static method | | str() | Returns a string object | | sum() | Sums up the numbers in the list | | super() | Returns an object that represents the parent class | | tuple() | Creates a tuple from an iterable or from individual elements | | type() | Returns the type of the object | | vars() | Returns the dict attribute of an object if the object has such an attribute | | zip() | zip() is a built-in function in Python that takes two or more iterables (such as lists, tuples, etc.) as arguments and returns an iterator of tuples |

1. abs() Function

The abs() function in Python is used to find the absolute value of a number. The absolute value of a number is its distance from zero on the number line. For example, the absolute value of -50 is 50.


# integer number     
integer = -50  
print('Absolute value of :', abs(integer))  

# Output
# Absolute value of : 50
  
# floating number  
floating = -50.28  
print('Absolute value of :', abs(floating))

# Output
# Absolute value of : 50.28

2. all() Function

The all() function in Python is used to determine whether all elements in an iterable (such as a list, tuple, or dictionary) are true. The function returns True if all elements in the iterable are true, and False otherwise.


# all values true  
List = [2, 4, 6, 8]  
print(all(List)) 

# Output
# True

# one false value  
List = [2, 4, 6, 8]  
print(all(List))  

# Output
# False

# one true value  
List = [0, False, 8]  
print(all(List))

# Output
# True  
  
# empty iterable  
List = []  
print(all(List)) 

# Output
# True

3. bin() Function

You can use the bin() function in Python to convert an integer number to its binary representation. The returned value is a string containing a binary number. The prefix '0b' is added to the string to indicate that the number is binary.


# Python bin() function
number = 20  
result = bin(number)  
print (result)

# Output
# 0b10100

4. bool()

You can use the bool() function in Python to convert a value to a Boolean (True or False) value. This function is used to check if a variable or expression is True or False.


# Use Python bool() 
test1 = []  
print(test1,'is',bool(test1)) 

# Output
[] is False

# Python bool() 
test1 = [0]  
print(test1,'is',bool(test1)) 

# Output
[0] is True

5. bytes()

The bytes() function in Python is used to create a bytes object. It returns a bytes object by encoding the string using the 'utf-8' encoding.


# Python bytes()
string = "Spark By Examples."  
array = bytes(string, 'utf-8')  
print(array)

# Output
# b'Spark By Examples.'

6. callable() Function

You can use the callable() function in Python to determine if an object is callable, meaning it can be invoked as a function. The function returns True if the object is callable, and False otherwise.


# Python callable() function
result = 15  
print(callable(result)) 

# Output
# False

7. exec() Function

You can use the exec() function in Python to execute a string of Python code. The string of code passed to the exec() function is treated as if it were a program and is executed.


# Python exec() function
x = 12  
exec('print(x==12)')  
exec('print(x+6)') 

# Output
# True
# 18

8. sum() Function

You can use the sum() function in python is used to get the sum of numbers of an iterable, i.e., list.


# Python sum() function
result = sum([2, 3, 4])  
print(result)  

# Output
# 9

# Use python sum
result = sum([2, 3, 4], 12)  
print(result)

# Output
# 21

9. any() Function

The any() function in Python returns True if at least one element in an iterable (e.g. list, tuple, etc.) is True. Otherwise, it returns False.


# Python any() function
result = [6, 4, 2, 0] 
print(any(result))

# Output
# True

10. ascii() Function

The ascii() function in Python returns a string containing a printable representation of an object. It's similar to the repr() function.


# Python ascii() function
result = 'Spark By Examples'  
print(ascii(result)) 

# Output
# 'Spark By Examples'

11. bytearray()

You can use the python bytearray() function is used to returns a bytearray object and can convert objects into bytearray objects, or create an empty bytearray object of the specified size.


# string with encoding 'utf-8'
string = "Spark By Examples."    
arr = bytearray(string, 'utf-8')  
print(arr)  

# Output
# bytearray(b'Spark By Examples.')

12. eval() Function

The eval() function in Python is used to evaluate a string as a Python expression. It takes a string as its argument and returns the result of the evaluated expression.


# Python eval() function
result = 15 
print(eval('result + 5')) 

# Output
# 20

13. float() Function

You can use the float() function in python is used to returns a floating-point number from a number or string.


# Python float() function
print(float(5.38))

# Output
# 5.38

14. format() Function

The python format() function is used to return a formatted representation of the given value.


# float arguments  
print(format(253.3567895, "f"))

# Output
# 253.356789

15. frozenset()

You can use the python frozenset() function to return an immutable frozenset object initialized with elements from the given iterable.


# tuple of letters  
letters = ('s', 'p', 'a', 'r', 'k')  
fSet = frozenset(letters)  
print('Frozen set is:', fSet)  
print('Empty frozen set is:', frozenset()) 

# Output
# Frozen set is: frozenset({'s', 'p', 'a', 'r', 'k'})
# Empty frozen set is: frozenset()

16. getattr() Function

The python gettr() function is used to return the value of a named attribute of an object.


# Python getattr() Function
class Details:  
    age = 35  
    name = "messi"  
  
details = Details()  
print('The age is:', getattr(details, "age"))  
print('The age is:', details.age) 

# Output
# The age is: 35
# The age is: 35

17. globals() Function

The Python globals() function is used to return a dictionary of the current global symbol table.


# Python globals() function
age = 35 
globals()['age'] = 35  
print('The age is:', age) 

# Output
# The age is: 35

18. hasattr() Function

You can use the hasattr() function in Python to check if an object has a given attribute. The function takes two arguments, the first is the object, and the second is the string name of the attribute. The function returns True if the object has the attribute and False if it does not.


# Python hasattr() function
class MyClass:
    x = 26

obj = MyClass()
result = hasattr(obj, 'x') 
print(result)

# Output
# True

# Use hasattr() function
result = hasattr(obj, 'y') 
print(result)

# Output
# False

19. iter() Function

The iter() function in Python is used to create an iterator object from an iterable (e.g. a list, a tuple, a string, etc.).


# Python iter() function
list = [2,4,6,8,7]    
listIter = iter(list)   
print(next(listIter)) 

# Output
# 2

20. len() Function

You can use the len() function in Python to return the number of items in an object. The function can be used with various types of objects, such as strings, lists, tuples, dictionaries, etc.


# Python len() function
String = 'aistudylabs'  
print(len(String))  

# Output
# 15

21. list() Function

You can use the list() function in Python to create a new list object. It can take an iterable object, such as a tuple or string, and convert it into a list.


# python list() function using string
string = "spark"
result = list(string)
print(result)

# Output
# ['s', 'p', 'a', 'r', 'k']

# Use tuple list
my_tuple = (2, 5, 8)
my_list = list(my_tuple)
print(my_list)

# Output
# [2, 5, 8]

22. locals() Function

The locals() function in Python is a built-in function that returns a dictionary of the current local symbol table. The keys in the dictionary are the names of local variables and the values are the values of the corresponding variables.


# python local() function
result = 25
locals()['result'] = 25
print(result)

# Output
# 25

23. map() Function

You can use Python map() function to apply the transformation function on each item of the iterable. We used to do this traditionally with for loop, but by using map() function you can avoid using explicit for loop in your code. Using the map() function makes your code readable and user-friendly. Try to avoid the looping when possible and use the map() function instead.

Related: Python reduce() Function

Let’s create a simple square() function and use it with map() function by taking a tuple of numbers. Here, is an example.


# Create tuple of numbers
numbers = (2, 4, 6, 8, 5)
print("Original:", numbers)

# Create function square
def square(x):
    return x * x

# Use map() function to apply a function
square_numbers = map(square, numbers)
result = list(square_numbers)
print("Result:",result)

# Output:
# Original: (2, 4, 6, 8, 5)
# Result: [4, 16, 36, 64, 25]

24. memoryview() Function

The memoryview() function in Python is a built-in function that returns a memory view object of the given argument. A memory view is a safe way to expose the internal data of an object to Python code without creating a copy.


#A random bytearray  
result = bytearray('SPARK', 'utf-8')  
mv = memoryview(result)  
  
# access the memory view's zeroth index  
print(mv[0])  
  
# It create byte from memory view  
print(bytes(mv[0:3]))  
  
# It create list from memory view  
print(list(mv[0:4]))

# Output
# 83
# b'SPA'
# [83, 80, 65, 82]

25. object()

The object() function in Python is a built-in function that returns a new object. This object is an instance of the object class, which is the base class for all classes in Python.


# Python object()
result = object()  
print(type(result))  
print(dir(result)) 

# Output
<class 'object'>
['__class__', '__delattr__', '__dir__', '__doc__', '__eq__', '__format__', '__ge__', '__getattribute__', '__gt__', '__hash__', '__init__', '__init_subclass__', '__le__', '__lt__', '__ne__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__']

26. open() Function

You can use open() function in Python to open a file for reading or writing. It takes two arguments: the first is the name or path of the file, and the second is a string that specifies the mode in which the file should be opened.


# opens python.text file of the current directory  
result = open("python.txt")  
# specifying full path  
result = open("C:/Python33/README.txt")

27. chr() Function

The chr() function in Python is used to return the string representing a character whose Unicode code point is the integer.


# It returns string 
# representation of a char  
result = chr(112)    
print(result)

# Output
# P

28. complex()

You can use the python complex() function to convert numbers or strings into complex numbers.


# Python complex() function
# Passing single parameter 
result = complex(3)    
print(result) 

# Output
(3+0j)

# Passing multiple parameters
result = complex(2,4) 
print(result) 

# Output
# (2+4j)

29. delattr() Function

The delattr() function in Python is used to delete an attribute from an object. It takes two arguments, the first is the object and the second is the string name of the attribute to be deleted.


# python delattr() function
class Student:  
    id = 122  
    name = "aistudylabs"  
    email = "aistudylabs.com"  
# Declaring function  
    def getinfo(self):  
        print(self.id, self.name, self.email)  
result = Student()  
result.getinfo()  
delattr(Student,'course') 
result.getinfo()

# Output
# AttributeError: course

30. dir() Function

The dir() function in Python returns a list of names in the current local scope or the object's namespace if an object is passed as an argument. This includes all attributes, methods, and variables that are defined in the object's class and any superclasses. If the object passed as an argument has a dir() method defined, this method will be called and must return a list of attributes.


# Python dir() function
result = dir()   
print(result)

# Output
# ['__annotations__', '__builtins__', '__cached__', '__doc__', '__file__', '__loader__', '__name__', '__package__', '__spec__']

31. divmod() Function

The divmod() function in Python returns a pair of numbers (a tuple) consisting of their quotient and remainder when using integer division. It takes two arguments, the first is the dividend and the second is the divisor.


# Python divmod() function
result = divmod(8,4)  
print(result)

# Output
# (2, 0)

32. enumerate() Function

You can use the enumerate() function in Python to iterate over a sequence (such as a list, tuple, or string) and return an iterator that produces tuples containing the index and the value of each element of the sequence.


# Python enumerate() function
result = enumerate([2,4,6])    
print(result)
print(list(result))

# Output
# <enumerate object at 0x148ec2f9a2c0>
# [(0, 2), (1, 4), (2, 6)]

33. dict() Function

The dict() function in Python is used to create a new dictionary. A dictionary is a data structure that stores key-value pairs, where each key is unique.


# Python dict() function 
result = dict() 
result2 = dict(a=3,b=5)  
print(result)  
print(result2) 

# Output
# {}
# {'a': 3, 'b': 5}

34. filter() Function

The filter() built-in function in Python is used to filter out elements from an iterable (such as a list, tuple, or string) that do not meet a certain condition.


# Python filter() function
def filterdata(x):  
    if x>5:  
        return x   
result = filter(filterdata,(2,4,8))   
print(list(result)) 

# Output
# [8]

35. hash() Function

You can use the Python hash() function to get the hash value of an object. Python calculates the hash value by using the hash algorithm. The resulting hash value is an integer and is used to compare dictionary keys during a dictionary lookup.


# Python hash() function 
# integer value
result = hash(25)   
print(result) 

# Output
# 25

# decimal value 
result2 = hash(27.4)   
print(result2)  

# Output
# 922337203685474331

36. help() Function

The help() function in Python is used to get help information related to a specific object or module. When called without any arguments, it opens the Python help console, which allows you to search for and view information about various modules and objects. When called with an argument, it returns help information for that specific object or module.


# Python help() function
info = help() 
print(info)

# Output
# Welcome to Python 3.8's help utility!

37. min() Function

You can use the min() function in Python to get the smallest item in an iterable or the smallest of two or more arguments. It takes one or more arguments, the first is a collection of elements and the second is key and returns the smallest element from the collection.


# Python min() function 
small = min(3335,325,2025)  
small2 = min(2000.25,2025.35,5625.36,10052.50)  
print(small)  
print(small2)

# Output
# 325
# 2000.25

38. set() Function

You can use the python set() function to create a new set object. A set is a collection of unique elements. The elements in a set can be of any type, including numbers, strings, and other objects. The order of elements in a set is not preserved.


# Python set() function
result = set('spark')   
print(result) 

# Output
# 'k', 'p', 'r', 's', 'a'}

39. hex() Function

You can use the hex() function in Python to convert an integer to a string representation of its hexadecimal value. The hexadecimal system uses base 16, and uses the digits 0-9 and the letters A-F to represent values.


# Python hex() function
result = hex(5)
print(result) 

# Output
# 0x5

# integer value  
result = hex(425)     
print(result)

# Output
# 0x1a9

40. id() Function

The id() function in Python is used to get the identity of an object. The identity is an unique integer that is assigned to an object during its creation and remains constant throughout its lifetime.


# Python id() function
# string object 
result = id("aistudylabs")  
print(result)  

# Output
# 23059105095920

# integer object 
result = id(1200)  
print(result)

# Output
# 23059106590064

41. setattr() Function

The setattr() function in Python is used to set the value of an attribute of an object, creating the attribute if it does not already exist.


# Python setattr() function
class Person:
    pass

result = Person()
setattr(result, 'name', 'messi')
print(result.name)

# Output
# messi

42. slice() Function

The slice() function in Python is used to create a slice object, which is used to extract a part of a sequence (e.g. a string, list, tuple, etc.).


# Python slice() function
# Using slice() to extract a part of a list
numbers = [2, 4, 6, 8, 1, 5, 9]
print(numbers[slice(2, 7)]) 

# Output
# [6, 8, 1, 5, 9]

# Using slice() to extract a part of a string
string = "aistudylabs!"
print(string[slice(5, 9)]) 

# Output
# byEx

43. sorted() Function

You can use the python built-in sorted() function to sort elements. By default, it sorts elements in ascending order but can be sorted in descending also. It takes four arguments and returns a new list after sorting.


# Python sorted() function  
str = "spark"  
result = sorted(str) 
print(result)

# Output
# ['a', 'k', 'p', 'r', 's']

44. next() Function

You can use the Python next() function to fetch next item from the collection. It takes two arguments, i.e., an iterator and a default value, and returns an element.


# Creating iterator 
number = iter([326, 52, 17])  
# Calling function  
item = next(number)   
# Displaying result  
print(item)  
# second item  
item = next(number)  
print(item)  
# third item  
item = next(number)  
print(item)

# Output
# 326
# 52
# 17

45. input() Function

The input() function in Python is used to read user input from the console.


# Python input() function
val = input("Enter a value: ")  
print("You entered:",val)

46. int() Function

The int() function in Python is used to convert a value to an integer. The value can be a string, a float, or another type of number, and the function will convert it to an integer.


# integer value
result = int(15) 
print(result)

# float value 
result = int(13.52) 
print(result)

# string value  
result = int('20') 
print(result)

# Output
# 15
# 13
# 20

47. isinstance() Function

You can use the isinstance() function in Python to determine if an object is an instance of a particular class or of a subclass thereof. The function takes two arguments: the object to be checked and the class or type to be checked against. If the object is an instance of the class or a subclass thereof, the function will return True, otherwise, it will return False.


# Python isinstance() function
class MyParent:
  pass

class MyChild(MyParent):
  pass

result = MyChild()
print(isinstance(result, MyParent))

# Output
# True

48. oct() Function

You can use the Python oct() function to get an octal value of an integer number. This function takes an argument and returns an integer converted into an octal string.


# Python oct() function
result = oct(30)  
print("Octal value of 30:",result) 

# Output
# Octal value of 30: 0o36

49. ord() Function

The ord() function in Python is used to return the integer representation of a character. The function takes a string of length one as an argument and returns its corresponding Unicode code point.


# Python ord() function
print(ord('9'))  
  
# Code point of an alphabet   
print(ord('M'))  
  
# Code point of a character  
print(ord('&')) 

# Output
# 57
# 77
# 38

50. pow() Function

You can use the python pow() function to calculate the power of a number. It takes two arguments, the base number, and the exponent. It returns the result of raising the base number to the power of the exponent.


# Python pow() Function
result = pow(2,5)
print(result)

# Output
# 32

# Use pow() Function
result = pow(3, 0.7)
print(result) 

# Output
# 2.157669279974593

51. print() Function

You can use the python print() function to output text or other data to the console. The text or data to be printed is passed as an argument to the function. For example


# Python print() function
print("aistudylabs")

# Output
# aistudylabs

52. range() Function

The range() function in Python is used to generate a sequence of numbers. This function takes three arguments: start, stop, and step. The start and step arguments are optional and default to 0 and 1 respectively.


# Generate a range of numbers from 0 to 5
for x in range(6):
    print(x)
    
# Output
# 0 1 2 3 4 5

# Convert range object to list
nums = list(range(3, 8))
print(nums)

# Output
# [3, 4, 5, 6, 7]

53. reversed() Function

You can use the python reversed() function to return the reversed iterator of the given sequence.


# Python reversed() function
# for string  
String = 'Spark'  
print(list(reversed(String)))  
  
# for tuple  
Tuple = ('S', 'p', 'a', 'r','k')  
print(list(reversed(Tuple))) 

# Output
# ['k', 'r', 'a', 'p', 'S']

54. round() Function

The round() function in Python is used to round off the digits of a number to a specified number of decimal places and returns the floating point number.


# Python round() function
# for integers  
print(round(20))  
  
# Output
# 20

# for floating point  
print(round(20.6))  

# Output
# 21
 
# even choice  
print(round(4.6)) 

# Output
# 5

55. issubclass() Function

The issubclass() function in Python is used to determine if a class is a subclass of a specified class.


class Rectangle:  
  def __init__(rectangleType):  
    print('Rectangle is a ', rectangleType)  
  
class Square(Rectangle):  
  def __init__(self):  
    Rectangle.__init__('square')  
      
print(issubclass(Square, Rectangle)) 

# Output
# True

56. Python str()

You can use the python str() to convert a specified value into a string.


# Use Python str()
str('7') 

# Output
# '7'

57. tuple() Function

The tuple() function in Python is used to create a tuple. A tuple is an immutable (non-modifiable) collection of elements, enclosed in parentheses and separated by commas. Tuples can contain elements of different types, such as integers, strings, and other objects.


# Creating a tuple with literals
result = tuple([3, 5, 7])
print(result) 

# Output
# (3, 5, 7)

# Creating an empty tuple
result = tuple()
print(result)

# Output
# ()

# Creating a tuple from a string
result = tuple("Spark")
print(result) 

# Output
# ('S', 'p', 'a', 'r', 'k')

# Creating a tuple from a list
list = [2,4,6,8]
result = tuple(list)
print(result)

# Output
# (2, 4, 6, 8)

58. type()

The type() function in Python is used to determine the type of an object. It takes an object as its only argument and returns the type of the object.


# python type()
List = [3, 5, 7]  
print(type(List))

# Output
# <class 'list'>

59. vars() Function

The vars() function in Python is used to return the dict attribute of an object if the object has a dict attribute. If the object does not have a dict attribute, vars() raises a TypeError.


# Python vars() function
class Python:  
  def __init__(self, x = 15, y = 20):  
    self.x = x  
    self.y = y      
result = Python()  
print(vars(result)) 

# Output
# {'x': 15, 'y': 20}

60. zip() Function

The Python zip() function is to used to combine multiple iterables into one iterable. It takes iterables (can be zero or more), makes it an iterator that aggregates the elements based on iterables passed, and returns an iterator of tuples.


# Python zip() function
list1 = [2, 4, 6]
list2 = [3, 5, 7]
zipped = zip(list1, list2)
print(list(zipped))

# Output
# [(2, 3), (4, 5), (6, 7)]

Conclusion

In this article, I have explained the list of the most used Python built-in functions and also explain each function with examples.

Happy Learning !!

References

https://docs.python.org/3/library/intro.html