Hướng dẫn geeksforgeeks python
Python is a general-purpose high-level programming language and is widely used among the developers’ community. Python was mainly developed for emphasis on code readability, and its syntax allows programmers to express concepts in fewer lines of code. This Python tutorial provides learners (either beginner or experienced developers) with topics from Python basics to advanced topics with examples. Show
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Key features of PythonPython has many reasons for being popular and in demand. A few of the reasons are mentioned below.
Application AreasGetting started with Python Tutorial –Python is a lot easier to code and learn. Python programs can be written on any plain text editor like notepad, notepad++, or anything of that sort. One can also use an online IDE for
writing Python codes or can even install one on their system to make it more feasible to write these codes because IDEs provide a lot of features like intuitive code editor, debugger, compiler, etc. What if Python already exists? Let’s checkWindows don’t come with Python preinstalled, it needs to be installed explicitly. But unlike windows, most of the Linux OS have Python pre-installed, also macOS comes with Python pre-installed. Now run the following command: python --version For Python3 python3 --version If Python is already installed, it will generate a message with the Python version available. Download and InstallationBefore starting with the installation process, you need to download it. For that all versions of Python for Windows, Linux, and MacOS are available on python.org. WindowsLinuxMacOSDownload the Python and follow the further instructions for the installation of Python. Beginning the installation. WindowsLinuxFor almost every Linux system, the following commands would work definitely. $ sudo add-apt-repository ppa:deadsnakes/ppa $ sudo apt-get update $ sudo apt-get install python3.8 To verify the installation enter following commands in your Terminal. python3 MacOS
How to run a Python programLet’s consider a simple Hello World Program. # Python program to print # Hello World print("Hello World") Generally, there are two ways to run a Python program.
WindowsOpen Commandline and then to compile the code type python HelloWorld.py. If your code has no error then it will execute properly and output will be displayed. Unix/LinuxOpen Terminal of your Unix/Linux OS and then to compile the code type python HelloWorld.py. If your code has no error then it will execute properly and output will be displayed. Fundamentals of PythonPython IndentationPython uses indentation to highlight the blocks of code. Whitespace is used for indentation in Python. All statements with the same distance to the right belong to the same block of code. If a block has to be more deeply nested, it is simply indented further to the right. You can understand it better by looking at the following lines of code. # Python program showing # indentation site = 'gfg' if site == 'gfg': print('Logging on to geeksforgeeks...') else: print('retype the URL.') print('All set !') Output: Logging on to geeksforgeeks... All set ! The lines Note: For more information, refer 👉🏽 Indentation in Python. Comments are useful information that the developers provide to make the reader understand the source code. It explains the logic or a part of it used in the code. There are two types of comment in Python:
Note: For more information, refer 👉🏽 Comments in Python. VariablesVariables in Python are not “statically typed”. We do not need to declare variables before using them or declare their type. A variable is created the moment we first assign a value to it. #!/usr/bin/python # An integer assignment age = 45 # A floating point salary = 1456.8 # A string name = "John" print(age) print(salary) print(name) Output: 45 1456.8 John Note: For more information, refer 👉🏽 Python Variables. OperatorsOperators are the main building block of any programming language. Operators allow the programmer to perform different kinds of operations on operands. These operators can be categorized based upon their different functionality:
Note: For more information, refer 👉🏽 Basic Operators in Python. Basics of Input/OutputTaking input from user –Python provides us with two inbuilt functions to read the input from the keyboard.
Note: For more information, refer 👉🏽 Python Printing output to console –The simplest way to produce output is using the # Python 3.x program showing # how to print data on # a screen # One object is passed print("GeeksForGeeks") x = 5 # Two objects are passed print("x =", x) # code for disabling the softspace feature print('G', 'F', 'G', sep ='') # using end argument print("Python", end = '@') print("GeeksforGeeks") Output: GeeksForGeeks x = 5 GFG [email protected] Data TypesData types are the classification or categorization of data items. It represents the kind of value that tells what operations can be performed on a particular data. Since everything is an object in Python programming, data types are actually classes and variables are instance (object) of these classes. NumericIn Python, numeric data type represent the data which has numeric value. Numeric value can be interger, floating number or even complex numbers. These values are defined as # Python program to # demonstrate numeric value print("Type of a: ", type(5)) print("\nType of b: ", type(5.0)) c = 2 + 4j print("\nType of c: ", type(c)) Output: Type of a: Sequence TypeIn Python, a sequence is the ordered collection of similar or different data types. Sequences allow storing multiple values in an organized and efficient fashion. There are several sequence types in Python –
1) String: A string is a collection of one or more characters put in a single quote, double-quote or triple quote. In python there is no character data type,
a character is a string of length one. It is represented by # Python Program for # Creation of String # String with single quotes print('Welcome to the Geeks World') # String with double quotes print("I'm a Geek") # String with triple quotes print('''I'm a Geek and I live in a world of "Geeks"''') Output: Welcome to the Geeks World I'm a Geek I'm a Geek and I live in a world of "Geeks" Accessing elements of string – # Python Program to Access # characters of String String1 = "GeeksForGeeks" # Printing First character print(String1[0]) # Printing Last character print(String1[-1]) Output: G s Deleting/Updating from a String – In Python, Updation or deletion of characters from a String is not allowed because Strings are immutable. Only new strings can be reassigned to the same name. # Python Program to Update / delete # character of a String String1 = "Hello, I'm a Geek" # Updating a character String1[2] = 'p' # Deleting a character del String1[2] Output: Traceback (most recent call last): File “/home/360bb1830c83a918fc78aa8979195653.py”, line 6, in String1[2] = ‘p’ TypeError: ‘str’ object does not support item assignment Traceback (most recent call last): File “/home/499e96a61e19944e7e45b7a6e1276742.py”, line 8, in del String1[2] TypeError: ‘str’ object doesn’t support item deletion Note: For more information, refer 👉🏽 Python String.
2) List: Lists are just like the arrays, declared in other languages. A single list may contain DataTypes like Integers, Strings, as well as Objects. The elements in a list are indexed according to a definite sequence and the indexing of a list is done with 0 being the first index. It is represented by # Python program to demonstrate # Creation of List # Creating a List List = [] print(List) # Creating a list of strings List = ['GeeksForGeeks', 'Geeks'] print(List) # Creating a Multi-Dimensional List List = [['Geeks', 'For'], ['Geeks']] print(List) Output: [] ['GeeksForGeeks', 'Geeks'] [['Geeks', 'For'], ['Geeks']] Adding
Elements to a List: Using # Python program to demonstrate # Addition of elements in a List # Creating a List List = [] # Using append() List.append(1) List.append(2) print(List) # Using insert() List.insert(3, 12) List.insert(0, 'Geeks') print(List) # Using extend() List.extend([8, 'Geeks', 'Always']) print(List) Output: [1, 2] ['Geeks', 1, 2, 12] ['Geeks', 1, 2, 12, 8, 'Geeks', 'Always'] Accessing elements from the List – Use the index operator # Python program to demonstrate # accessing of element from list List = [1, 2, 3, 4, 5, 6] # accessing a element print(List[0]) print(List[2]) # Negative indexing # print the last element of list print(List[-1]) # print the third last element of list print(List[-3]) Output: 1 3 6 4 Removing Elements from the
List: Using # Python program to demonstrate # Removal of elements in a List # Creating a List List = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12] # using Remove() method List.remove(5) List.remove(6) print(List) # using pop() List.pop() print(List) Output: [1, 2, 3, 4, 7, 8, 9, 10, 11, 12] [1, 2, 3, 4, 7, 8, 9, 10, 11] Note: For more information, refer 👉🏽 Python List.
3) Tuple: Tuple is an ordered collection of Python objects
much like a list. The important difference between a list and a tuple is that tuples are immutable. It is represented by # Python program to demonstrate # creation of Set # Creating an empty tuple Tuple1 = () print (Tuple1) # Creating a tuple of strings print(('Geeks', 'For')) # Creating a Tuple of list print(tuple([1, 2, 4, 5, 6])) # Creating a nested Tuple Tuple1 = (0, 1, 2, 3) Tuple2 = ('python', 'geek') Tuple3 = (Tuple1, Tuple2) print(Tuple3) Output: () ('Geeks', 'For') (1, 2, 4, 5, 6) ((0, 1, 2, 3), ('python', 'geek')) Accessing element of a tuple – Use the index operator # Python program to # demonstrate accessing tuple tuple1 = tuple([1, 2, 3, 4, 5]) # Accessing element using indexing print(tuple1[0]) # Accessing element using Negative # Indexing print(tuple1[-1]) Output: 1 5 Deleting/updating elements of tuple – Items of a tuple cannot be deleted as tuples are immutable in Python. Only new tuples can be reassigned to the same name. # Python program to # demonstrate updation / deletion # from a tuple tuple1 = tuple([1, 2, 3, 4, 5]) # Updating an element tuple1[0] = -1 # Deleting an element del tuple1[2] Output: Traceback (most recent call last): File "/home/084519a8889e9b0103b874bbbb93e1fb.py", line 11, in tuple1[0] = -1 TypeError: 'tuple' object does not support item assignment Traceback (most recent call last): File "/home/ffb3f8be85dd393bde5d0483ff191343.py", line 12, in del tuple1[2] TypeError: 'tuple' object doesn't support item deletion Note: For more information, refer 👉🏽 Python Tuples.
BooleanBooleans are data type with one of the two built-in values, # Python program to # demonstrate boolean type print(type(True)) print(1>2) print('a'=='a') Output:
SetIn Python, Set is an unordered collection of data type that is iterable, mutable and has no duplicate elements. The order of elements in a set is undefined though it may consist of various elements. Sets can be created by using the built-in # Python program to demonstrate # Creation of Set in Python # Creating a Set set1 = set() # Creating a Set of String set1 = set("GeeksForGeeks") print(set1) # Creating a Set of List set1 = set(["Geeks", "For", "Geeks"]) print(set1) Output: {'o', 'r', 'k', 'G', 'e', 's', 'F'} {'Geeks', 'For'} Adding elements: Using # Python program to demonstrate # Addition of elements in a Set set1 = set() # Adding to the Set using add() set1.add(8) set1.add((6, 7)) print(set1) # Additio to the Set using Update() set1.update([10, 11]) print(set1) Output: {8, (6, 7)} {8, 10, 11, (6, 7)} Accessing a Set: One can loop through the set items using a # Python program to demonstrate # Accessing of elements in a set # Creating a set set1 = set(["Geeks", "For", "Geeks"]) # Accessing using for loop for i in set1: print(i, end =" ") Output: Geeks For Removing
elements from a set: Using # Python program to demonstrate # Deletion of elements in a Set set1 = set([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]) # using Remove() method set1.remove(5) set1.remove(6) print(set1) # using Discard() method set1.discard(8) set1.discard(9) print(set1) # Set using the pop() method set1.pop() print(set1) # Set using clear() method set1.clear() print(set1) Output: {1, 2, 3, 4, 7, 8, 9, 10, 11, 12} {1, 2, 3, 4, 7, 10, 11, 12} {2, 3, 4, 7, 10, 11, 12} set() Note: For more information, refer 👉🏽 Python Sets.
DictionaryDictionary in Python is an unordered collection of data
values, used to store data values like a map. Dictionary holds # Creating an empty Dictionary Dict = {} print(Dict) # with Integer Keys Dict = {1: 'Geeks', 2: 'For', 3: 'Geeks'} print(Dict) # with Mixed keys Dict = {'Name': 'Geeks', 1: [1, 2, 3, 4]} print(Dict) Output: {} {1: 'Geeks', 2: 'For', 3: 'Geeks'} {1: [1, 2, 3, 4], 'Name': 'Geeks'} Nested Dictionary: # Creating a Nested Dictionary # as shown in the below image Dict = {1: 'Geeks', 2: 'For', 3:{'A' : 'Welcome', 'B' : 'To', 'C' : 'Geeks'}} print(Dict) Output: {1: 'Geeks', 2: 'For', 3: {'A': 'Welcome', 'B': 'To', 'C': 'Geeks'}} Note: For more information, refer 👉🏽 Python Nested Dictionary. Adding elements to a Dictionary: One value at a time can be added to a Dictionary by defining value along with the key e.g. # Creating an empty Dictionary Dict = {} # Adding elements one at a time Dict[0] = 'Geeks' Dict[2] = 'For' Dict[3] = 1 print(Dict) # Updating existing Key's Value Dict[2] = 'Welcome' print(Dict) Output: {0: 'Geeks', 2: 'For', 3: 1} {0: 'Geeks', 2: 'Welcome', 3: 1} Accessing elements from a Dictionary: In order to access the items of a dictionary refer to its key name or use # Python program to demonstrate # accessing an element from a Dictionary # Creating a Dictionary Dict = {1: 'Geeks', 'name': 'For', 3: 'Geeks'} # accessing a element using key print(Dict['name']) # accessing a element using get() print(Dict.get(3)) Output: For Geeks Removing Elements from Dictionary: Using # Initial Dictionary Dict = { 5 : 'Welcome', 6 : 'To', 7 : 'Geeks', 'A' : {1 : 'Geeks', 2 : 'For', 3 : 'Geeks'}, } # using pop() Dict.pop(5) print(Dict) # using popitem() Dict.popitem() print(Dict) Output: {'A': {1: 'Geeks', 2: 'For', 3: 'Geeks'}, 6: 'To', 7: 'Geeks'} {6: 'To', 7: 'Geeks'} Note: For more information, refer 👉🏽 Python Dictionary.
Decision MakingDecision Making in programming is similar to decision making in real life. A programming language uses control statements to control the flow of execution of the program based on certain conditions. These are used to cause the flow of execution to advance and branch based on changes to the state of a program. Decision-making statements in Python
Example 1: To demonstrate # Python program to demonstrate # decision making a = 10 b = 15 # if to check even number if a % 2 == 0: print("Even Number") # if-else to check even or odd if b % 2 == 0: print("Even Number") else: print("Odd Number") Output: Even Number Odd Number Example 2: To demonstrate # Python program to demonstrate # decision making a = 10 # Nested if to check whether a # number is divisible by both 2 and 5 if a % 2 == 0: if a % 5 == 0: print("Number is divisible by both 2 and 5") # is-elif if (a == 11): print ("a is 11") elif (a == 10): print ("a is 10") else: print ("a is not present") Output: Number is divisible by both 2 and 5 a is 10 Note: For more information, refer 👉🏽 Decision Making in Python. Control flow (Loops)Loops in programming come into use when we need to repeatedly execute a block of statements. For example: Suppose we want to print “Hello World” 10 times. This can be done with the help of loops. The loops in Python are:
Loop control statementsLoop control statements change execution from its normal sequence. Following are the loop control statements provided by Python:
# Python program to demonstrate # break, continue and pass s = 'geeksforgeeks' for letter in s: if letter == 'e' or letter == 's': break print(letter, end = " ") print() for letter in s: if letter == 'e' or letter == 's': continue print(letter, end = " ") print() for letter in s: if letter == 'e' or letter == 's': pass print(letter, end = " ") Output: g g k f o r g k g e e k s f o r g e e k s Note: For more information, refer 👉🏽 break, continue and pass in Python. FunctionsFunctions are generally the block of codes or statements in a program that gives the user the ability to reuse the same code which
ultimately saves the excessive use of memory, acts as a time saver and more importantly, provides better readability of the code. So basically, a function is a collection of statements that perform some specific task and return the result to the caller. A function can also perform some specific task without returning anything. In Python, # Python program to demonstrate # functions # Defining functions def ask_user(): print("Hello Geeks") # Function that returns sum # of first 10 numbers def my_func(): a = 0 for i in range(1, 11): a = a + i return a # Calling functions ask_user() res = my_func() print(res) Output: Hello Geeks 55 Function with arguments
Note: For more information, refer 👉🏽 Functions in Python.
Lambda functionsIn Python, the lambda/anonymous function means that a function is without a name. The # Python code to demonstrate # labmda function # Cube using lambda cube = lambda x: x * x*x print(cube(7)) # List comprehension using lambda a = [(lambda x: x * 2)(x) for x in range(5)] print(a) Output: 343 [0, 2, 4, 6, 8] Note: For more information, refer 👉🏽 Python lambda (Anonymous Functions).
Object Oriented ProgrammingObject-oriented programming aims to implement real-world entities like inheritance, hiding, polymorphism, etc in programming. The main aim of OOP is to bind together the data and the functions that operate on them so that no other part of the code can access this data except that function. Classes and ObjectsClass creates a user-defined data structure, which holds its own data members and member functions, which can be accessed and used by creating an instance of that class. A class is like a blueprint for an object. An Object is an instance of a Class. A class is like a blueprint while an instance is a copy of the class with actual values. # Python program to demonstrate # classes and objects class Dog: # A simple class attribute attr1 = "mamal" attr2 = "dog" # A sample method def fun(self): print("I'm a", self.attr1) print("I'm a", self.attr2) # Driver code # Object instantiation Rodger = Dog() # Accessing class attributes # and method through objects print(Rodger.attr1) Rodger.fun() Output: mamal I'm a mamal I'm a dog Note: For more information, refer 👉🏽 Python Classes and Objects. The self self represents the instance of the class. By using the “ Note: For more information, refer 👉🏽 self in Python class. Constructors and DestructorsConstructors: Constructors are generally used for instantiating an object.The task of constructors is to initialize(assign values) to the data members of the class when an object of class is created. In Python the
# Python program to demonstrate # constructors class Addition: # parameterized constructor def __init__(self, f, s): self.first = f self.second = s def calculate(self): print(self.first + self.second) # Invoking parameterized constructor obj = Addition(1000, 2000) # perform Addition obj.calculate() Output: 3000 Note: For more information, refer 👉🏽 Constructors in Python. Destructors: Destructors are called when an object gets destroyed. The # Python program to illustrate destructor class Employee: # Initializing def __init__(self): print('Employee created.') # Deleting (Calling destructor) def __del__(self): print('Destructor called, Employee deleted.') obj = Employee() del obj Output: Employee created. Destructor called, Employee deleted. Note: For more information, refer 👉🏽 Destructors in Python. InheritanceInheritance is the ability of any class to extract and use features of other classes. It is the process by which new classes called the derived classes are created from existing classes called Base classes. # A Python program to demonstrate inheritance class Person(): # Constructor def __init__(self, name): self.name = name # To get name def getName(self): return self.name # To check if this person is employee def isEmployee(self): return False # Inherited or Sub class (Note Person in bracket) class Employee(Person): # Here we return true def isEmployee(self): return True # Driver code emp = Person("Geek1") # An Object of Person print(emp.getName(), emp.isEmployee()) emp = Employee("Geek2") # An Object of Employee print(emp.getName(), emp.isEmployee()) Output: Geek1 False Geek2 True Note: For more information, refer 👉🏽 Python inheritance. EncapsulationEncapsulation describes the idea of wrapping data and the methods that work on data within one unit. This puts restrictions on accessing variables and methods directly and can prevent the accidental modification of data. # Python program to demonstrate # encapsulation # Creating a Base class class Base: def __init__(self): self.a = "GeeksforGeeks" self.__c = "GeeksforGeeks" # Creating a derived class class Derived(Base): def __init__(self): # Calling constructor of # Base class Base.__init__(self) print("Calling private member of base class: ") print(self.__a) # Driver code obj = Derived() Output: Traceback (most recent call last): File "/home/5a605c59b5b88751d2b93dd5f932dbd5.py", line 20, in obj = Derived() File "/home/5a605c59b5b88751d2b93dd5f932dbd5.py", line 18, in __init__ print(self.__a) AttributeError: 'Derived' object has no attribute '_Derived__a' Note: For more information, refer 👉🏽 Encapsulation in Python. PolymorphismPolymorphism refers to the ability of OOPs programming languages to differentiate between entities with the same name efficiently. This is done by Python with the help of the signature of these entities. # Python program to demonstrate # Polymorphism class A(): def show(self): print("Inside A") class B(): def show(self): print("Inside B") # Driver's code a = A() a.show() b = B() b.show() Output: Inside A Inside B
File HandlingFile handling is the ability of Python to handle files i.e. to read and write files along with many other file handling options. Python treats files differently as text or binary and this is important. Each line of code includes a sequence of characters and they form a text file. Each line of a file is terminated with a special character, called the EOL or End of Line
characters like comma Basic File Handling operations in Python are: 1) Open a file: Opening a file refers to getting the file ready either for reading or for writing. This can be done using the
# Open function to open the file "MyFile1.txt" # (same directory) in read mode and file1 = open("MyFile.txt", "r") # store its reference in the variable file1 # and "MyFile2.txt" in D:\Text in file2 file2 = open(r"D:\Text\MyFile2.txt", "r+") Note: For more information, refer 👉🏽 Open a File in Python. 2) Close the file: # Opening and Closing a file "MyFile.txt" # for object name file1. file1 = open("MyFile.txt", "a") file1.close() 3) Reading from a File: There are three ways to read data from a text file.
Let’s suppose the file looks like this: # Program to show various ways to # read data from a file. file1 = open("data.txt", "r+") print("Output of Read function is ") print(file1.read()) print() # seek(n) takes the file handle to the nth # bite from the beginning. file1.seek(0) print("Output of Readline function is ") print(file1.readline()) print() file1.seek(0) # readlines function print("Output of Readlines function is ") print(file1.readlines()) print() file1.close() Output: Output of Read function is Code is like humor. When you have to explain it, its bad. Output of Readline function is Code is like humor. When you have to explain it, its bad. Output of Readlines function is ['Code is like humor. When you have to explain it, its bad.'] Note: For more information, refer 👉🏽 How to read from a file in Python. 4) Writing to a file: There are two ways to write in a file.
# Python program to demonstrate # writing to file # Opening a file file1 = open('myfile.txt', 'w') L = ["This is Delhi \n", "This is Paris \n", "This is London \n"] s = "Hello\n" # Writing a string to file file1.write(s) # Writing multiple strings # at a time file1.writelines(L) # Closing file file1.close() Output: Note: For more information, refer 👉🏽 Writing to file in Python.
Modules and PackagesModulesA module is a self-contained Python file that contains Python statements and definitions, like a file named Let’s create a simple module named GFG. # Python program to demonstrate # modules # Defining a function def Geeks(): print("GeeksforGeeks") # Defining a variable location = "Noida" # Defining a class class Employee(): def __init__(self, name, position): self. name = name self.position = position def show(self): print("Employee name:", self.name) print("Employee position:", self.position) To use the above created module, create a new Python file in the same directory and import GFG module using the # Python program to demonstrate # modules import GFG # Use the function created GFG.Geeks() # Print the variable declared print(GFG.location) # Use the class created emp = GFG.Employee("Nikhil", "Developer") emp.show() Output: GeeksforGeeks Noida Employee name: Nikhil Employee position: Developer Note: For more information, refer 👉🏽 Python Modules. PackagesPackages are a way of structuring many packages and modules which helps in a well-organized hierarchy of data set, making the directories and modules easy to access. To create a package in Python, we need to follow these three simple steps:
Example: Let’s create a package for cars.
Now, let’s use the package that we created. To do this make a sample.py file in the same directory where Cars package is located and add the following code to it: # Import classes from your brand new package from Cars import Bmw from Cars import Audi # Create an object of Bmw class & call its method ModBMW = Bmw() ModBMW.outModels() # Create an object of Audi class & call its method ModAudi = Audi() ModAudi.outModels() Output: Note: For more information, refer 👉🏽 Create and Access a Python Package. Regular expressions(RegEx)Python RegEx is a powerful text matching tool that uses a pre-defined pattern to match the text. It can identify the presence or absence of text by comparing it to a specific pattern, and it can also divide a pattern into one or more sub-patterns. Below is the list of metacharacters: \ Used to drop the special meaning of character following it (discussed below) [] Represent a character class ^ Matches the beginning $ Matches the end . Matches any character except newline ? Matches zero or one occurrence. | Means OR (Matches with any of the characters separated by it. * Any number of occurrences (including 0 occurrences) + One ore more occurrences {} Indicate the number of occurrences of a preceding RE to match. () Enclose a group of REs The most frequently used methods are:
Note: For more information, refer 👉🏽 Regular Expression in Python. Exception handlingLike other languages, Python also provides the runtime errors via exception handling method with the help of try-except. How try-except works?
Code 1: No exception, so try clause will run. # Python code to illustrate # working of try() def divide(x, y): try: result = x // y print("Yeah ! Your answer is :", result) except ZeroDivisionError: print("Sorry ! You are dividing by zero ") # Look at parameters and note the working of Program divide(3, 2) Output: Yeah ! Your answer is : 1 Code 2: There is an exception so only except clause will run. # Python code to illustrate # working of try() def divide(x, y): try: result = x // y print("Yeah ! Your answer is :", result) except: print("Sorry ! You are dividing by zero ") # Look at parameters and note the working of Program divide(3, 0) Output: Sorry ! You are dividing by zero Else Clause: In python, you can also use else clause on try-except block which must be present after all the except clauses. The code enters the else block only if the try clause does not raise an exception. # Python code to illustrate # working of try() def divide(x, y): try: result = x // y print("Yeah ! Your answer is :", result) except: print("Sorry ! You are dividing by zero ") else: print("No exception raised") # Look at parameters and note the working of Program divide(3, 2) Output: Yeah ! Your answer is : 1 No exception raised Raising Exception: The raise statement allows the programmer to force a specific exception to occur. This must be either an exception instance or an exception class. To know more about the list of exception class 👉🏽 click here. # Program to depict Raising Exception try: raise NameError("Hi there") # Raise Error except NameError: print("An exception") raise # To determine whether the exception was raised or not Output: Traceback (most recent call last): File "/home/4678cd3d633b2ddf9d19fde6283f987b.py", line 4, in raise NameError("Hi there") # Raise Error NameError: Hi there Note: For more information, refer 👉🏽 Python exception handling. |