To do that, modify the if __name__ == __main__ part of file_one to look like this: Now let's say the file_two module is really big with lot of functions (two in our case), and you don't want to import all of them. p1.age = 40 You can make a tax-deductible donation here. Learn more about bidirectional Unicode characters. # module will then lazily import from the modules that implement the objects. p1, class Person: self.name = name def __init__(self, name, age):
print(p1.name) To run one of these functions modify the if __name__ == "__main__" part of file_one to look like this: When running file_one you should see should be like this: Also, you can run functions from imported files. This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. All rights reserved. If you follow this article step-by-step and read its code snippets, you will learn how to use if __name__ == "__main__", and why it's so important. 085-350-7540 , 084-88-00-255 , ntprintf@gmail.com, Expert Programming Tutor Class and Objects, class Person, , LM73PYTHON HOWTO REMOVE DUPLICATES FROM A PYTHON LIST, LM74PYTHON HOW TO REVERSE A STRING IN PYTHON, LM75PYTHON HOW TO ADD TWO NUMBERS IN PYTHON, https://www.w3schools.com/python/python_classes.asp, https://elearn.expert-programming-tutor.com, 9 Reasons Your Child Should Learn to Code, 14 What Will AIs Biggest Contribution To Healthcare Be, MT003 8 Fun Machine Learning Projects For Beginner, MT006 Top 20 Python Machine Learning Open Source Projects, MT102 Introduction to Deep Learning with TensorFlow, MT103 Installing TensorFlow for Deep Learning, MT104 TensorFlow Creating the Neural Network Model, MT105 TensorFlow How the Network will run, MT203 How to program a quantum computer PART1, MT204 How to program a quantum computer PART2, LM16PYTHON 10NUMPY TRIGONOMETRIC FUNCTIONS, LM18PYTHON MACHINE LEARNING MEAN MEDIAN MODE, LM19PYTHON MACHINE LEARNING STANDARD DEVIATION, LM21PYTHON MACHINE LEARNING DATA DISTRIBUTION, LM22PYTHON MACHINE LEARNING NORMAL DATA DISTRIBUTION, LM24PYTHON MACHINE LEARNING LINEAR REGRESSION, LM25PYTHON MACHINE LEARNING MULTIPLE REGRESSION, LM25PYTHON MACHINE LEARNING POLYNOMIAL REGRESSION, LM28PYTHON MACHINE LEARNING DECISION TREE, VDO0003 PY801 Data Sci Data Analyst with Python 01, VDO0004 PY801 Data Sci Data Analyst with Python 02, VDO0006 Lets Learn Web Programming Easy Version, Course SET Course , Course Level Up - , Course Level Up - (), Course ESSENTIAL COURSE ( Private ), Course 1-2 . x = 5 def myfunc(self): print(p1.age), Delete Object Properties __init __ () __init __ () __init __ () All of the provided, classes are independent from each other so you can mix it with any other. 026-111-618 Attribute access to the werkzeug.
def myfunc(self):
But now the variable __name__ in file_two is set as its module name, hence file_two. File "demo_class7.py", line 13, in # Due to bootstrapping issues we need to import exceptions here. Object Methods del() Reading the file executes all top level code, but not functions and classes (since they will only get imported). File "demo_class8.py", line 13, in But the __name__ variable for all other modules that are being imported will be set to their module's name. class object p1, class Person:
def __init__(self, name, age): freeCodeCamp's open source curriculum has helped more than 40,000 people get jobs as developers. # the version. It provides useful classes and functions for any WSGI application to make, the life of a python web developer much easier. print(p1) MyClass , class MyClass: class Person
| 085-350-7540 | 084-88-00-255 | ntprintf@gmail.com, . print(p1.age), Traceback (most recent call last): print("Hello my name is " + self.name)
We accomplish this by creating thousands of videos, articles, and interactive coding lessons - all freely available to the public. A module can define functions, classes, and variables. del()
Person __init __ () , class Person: Werkzeug is the Swiss Army knife of Python web development. self.age = age print(p1.age), : __init __ ()
self.name = name You signed in with another tab or window.
:copyright: (c) 2014 by the Werkzeug Team, see AUTHORS for more details.
Software enginner with experience in developing, testing and maintaining software solutions. print("Hello my name is " + self.name) p1 = Person("John", 36) Now run file_two and you will see that the __name__ variable is set to __main__: When modules like this are being imported and run, their functions will be imported, and top level code executed.
AttributeError: 'Person' object has no attribute 'age', : self p1, Delete Objects NameError: 'p1' is not defined, The pass Statement print(p1.age), Traceback (most recent call last): self.age = age But if the code is importing the module from another module, then the __name__ variable will be set to that modules name. There is no useful grouping for those which is why, # they are all importable from "werkzeug" instead of the modules where they are, # implemented. Bra gjort!
To review, open the file in an editor that reveals hidden Unicode characters.
def __init__(self, name, age): Let's take a look at an example. def __init__(self, name, age): p1.age = 40
# and motivation is explained here in detail now.
(That means "Well done" in Swedish!). p1 = MyClass() # This import magic raises concerns quite often which is why the implementation. p1 = Person("John", 36) But run file_two directly and you will see that its name is set to __main__: The variable __name__ for the file/module that is run will be always __main__. MyClass x, Objects # The majority of the functions and classes provided by Werkzeug work on the, # HTTP and WSGI layer.
del p1.age The usual way of using __name__ and __main__ looks like this: Let's see how this works in real life, and how to actually use these variables. self.name = name Python files are called modules and they are identified by the .py file extension. pass This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository. self.age = age # having an empty class definition like this, would raise an error without the pass statement, Class and Objects """, # keep a reference to this module so that it's not garbage collected, # setup the new module and patch it into the dict of loaded modules.
The variable __name__ for this module is set to __main__: Now add another file named file_two.py and paste this code inside: Also, modify the code in file_one.py like this so we import the file_two module: Running our file_one code once again will show that the __name__ variable in the file_one did not change, and still remains set to __main__.
To see this process in action, modify your files to look like this: Now the functions are loaded but not run. print("Hello my name is " + self.name), p1 = Person("John", 36) Modify file_one and file_two to look like this: Again, when running file_one you will see that the program recognized which of these two modules is __main__ and executed the code according to our first if else statements. self.name = name del p1.age EMAIL: NTPRINTF@GMAIL.COM, Copyright (c) 2013 expert-programming-tutor.com. Python Python Class "blueprint"" The downside of that is, that now everything would be loaded at, # The implementation of a lazy-loading module in this file replaces the, # werkzeug package when imported from within. print("Hello my name is " + self.name), p1 = Person("John", 36) Donations to freeCodeCamp go toward our education initiatives, and help pay for servers, services, and staff. Working in agile, entrepreneurial, high paced global company. Cannot retrieve contributors at this time. We can use an if __name__ == "__main__" block to allow or prevent parts of code from being run when the modules are imported. Modify file_two to look like this: And to import the specific functions from the module, use the from import block in the file_one file: There is a really nice use case for the __name__ variable, whether you want a file that can be run as the main program or imported by other modules. One of those variables is called __name__. Get started, freeCodeCamp is a donor-supported tax-exempt 501(c)(3) nonprofit organization (United States Federal Tax Identification Number: 82-0779546). # import mapping to objects in other modules, # modules that should be imported when accessed as attributes of werkzeug, """Automatically import objects from the modules. p1 40, class Person: mysillyobject abc self, class Person: def __init__(self, name, age): :license: BSD, see LICENSE for more details. We also have thousands of freeCodeCamp study groups around the world. https://www.w3schools.com/python/python_classes.asp, 085-350-7540 (DTAC)
When the Python interpreter reads a file, the __name__ variable is set as __main__ if the module being run, or as the module's name if it is imported. When a Python interpreter reads a Python file, it first sets a few special variables. print(p1.age), Modify Object Properties self.age = age
class class pass Error print(p1.x), __init __ () self.name = name self.age = age, def myfunc(self): Create a Python module named file_one.py and paste this top level code inside: By running this file you will see exactly what we were talking about. Check out more articles like this on my freeCodeCamp profile, Medium profile, and other fun stuff I build on my GitHub page. print(p1.age) The self Parameter
class Learn to code for free.
Our mission: to help people learn to code for free. 084-88-00-255 (AIS) Then it executes the code from the file.
def myfunc(self):
Expert Programming Tutor Class and Objects Usually set automatically by a script. p1 = Person("John", 36) So when the interpreter runs a module, the __name__ variable will be set as __main__ if the module that is being run is the main program. , class Person:
print(p1.name) To run one of these functions modify the if __name__ == "__main__" part of file_one to look like this: When running file_one you should see should be like this: Also, you can run functions from imported files. This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. All rights reserved. If you follow this article step-by-step and read its code snippets, you will learn how to use if __name__ == "__main__", and why it's so important. 085-350-7540 , 084-88-00-255 , ntprintf@gmail.com, Expert Programming Tutor Class and Objects, class Person, , LM73PYTHON HOWTO REMOVE DUPLICATES FROM A PYTHON LIST, LM74PYTHON HOW TO REVERSE A STRING IN PYTHON, LM75PYTHON HOW TO ADD TWO NUMBERS IN PYTHON, https://www.w3schools.com/python/python_classes.asp, https://elearn.expert-programming-tutor.com, 9 Reasons Your Child Should Learn to Code, 14 What Will AIs Biggest Contribution To Healthcare Be, MT003 8 Fun Machine Learning Projects For Beginner, MT006 Top 20 Python Machine Learning Open Source Projects, MT102 Introduction to Deep Learning with TensorFlow, MT103 Installing TensorFlow for Deep Learning, MT104 TensorFlow Creating the Neural Network Model, MT105 TensorFlow How the Network will run, MT203 How to program a quantum computer PART1, MT204 How to program a quantum computer PART2, LM16PYTHON 10NUMPY TRIGONOMETRIC FUNCTIONS, LM18PYTHON MACHINE LEARNING MEAN MEDIAN MODE, LM19PYTHON MACHINE LEARNING STANDARD DEVIATION, LM21PYTHON MACHINE LEARNING DATA DISTRIBUTION, LM22PYTHON MACHINE LEARNING NORMAL DATA DISTRIBUTION, LM24PYTHON MACHINE LEARNING LINEAR REGRESSION, LM25PYTHON MACHINE LEARNING MULTIPLE REGRESSION, LM25PYTHON MACHINE LEARNING POLYNOMIAL REGRESSION, LM28PYTHON MACHINE LEARNING DECISION TREE, VDO0003 PY801 Data Sci Data Analyst with Python 01, VDO0004 PY801 Data Sci Data Analyst with Python 02, VDO0006 Lets Learn Web Programming Easy Version, Course SET Course , Course Level Up - , Course Level Up - (), Course ESSENTIAL COURSE ( Private ), Course 1-2 . x = 5 def myfunc(self): print(p1.age), Delete Object Properties __init __ () __init __ () __init __ () All of the provided, classes are independent from each other so you can mix it with any other. 026-111-618 Attribute access to the werkzeug.
def myfunc(self):
But now the variable __name__ in file_two is set as its module name, hence file_two. File "demo_class7.py", line 13, in # Due to bootstrapping issues we need to import exceptions here. Object Methods del() Reading the file executes all top level code, but not functions and classes (since they will only get imported). File "demo_class8.py", line 13, in But the __name__ variable for all other modules that are being imported will be set to their module's name. class object p1, class Person:
def __init__(self, name, age): freeCodeCamp's open source curriculum has helped more than 40,000 people get jobs as developers. # the version. It provides useful classes and functions for any WSGI application to make, the life of a python web developer much easier. print(p1) MyClass , class MyClass: class Person
| 085-350-7540 | 084-88-00-255 | ntprintf@gmail.com, . print(p1.age), Traceback (most recent call last): print("Hello my name is " + self.name)
We accomplish this by creating thousands of videos, articles, and interactive coding lessons - all freely available to the public. A module can define functions, classes, and variables. del()
Person __init __ () , class Person: Werkzeug is the Swiss Army knife of Python web development. self.age = age print(p1.age), : __init __ ()
self.name = name You signed in with another tab or window.
:copyright: (c) 2014 by the Werkzeug Team, see AUTHORS for more details.
Software enginner with experience in developing, testing and maintaining software solutions. print("Hello my name is " + self.name) p1 = Person("John", 36) Now run file_two and you will see that the __name__ variable is set to __main__: When modules like this are being imported and run, their functions will be imported, and top level code executed.
AttributeError: 'Person' object has no attribute 'age', : self p1, Delete Objects NameError: 'p1' is not defined, The pass Statement print(p1.age), Traceback (most recent call last): self.age = age But if the code is importing the module from another module, then the __name__ variable will be set to that modules name. There is no useful grouping for those which is why, # they are all importable from "werkzeug" instead of the modules where they are, # implemented. Bra gjort!
To review, open the file in an editor that reveals hidden Unicode characters.
def __init__(self, name, age): Let's take a look at an example. def __init__(self, name, age): p1.age = 40
# and motivation is explained here in detail now.
(That means "Well done" in Swedish!). p1 = MyClass() # This import magic raises concerns quite often which is why the implementation. p1 = Person("John", 36) But run file_two directly and you will see that its name is set to __main__: The variable __name__ for the file/module that is run will be always __main__. MyClass x, Objects # The majority of the functions and classes provided by Werkzeug work on the, # HTTP and WSGI layer.
del p1.age The usual way of using __name__ and __main__ looks like this: Let's see how this works in real life, and how to actually use these variables. self.name = name Python files are called modules and they are identified by the .py file extension. pass This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository. self.age = age # having an empty class definition like this, would raise an error without the pass statement, Class and Objects """, # keep a reference to this module so that it's not garbage collected, # setup the new module and patch it into the dict of loaded modules.
The variable __name__ for this module is set to __main__: Now add another file named file_two.py and paste this code inside: Also, modify the code in file_one.py like this so we import the file_two module: Running our file_one code once again will show that the __name__ variable in the file_one did not change, and still remains set to __main__.
To see this process in action, modify your files to look like this: Now the functions are loaded but not run. print("Hello my name is " + self.name), p1 = Person("John", 36) Modify file_one and file_two to look like this: Again, when running file_one you will see that the program recognized which of these two modules is __main__ and executed the code according to our first if else statements. self.name = name del p1.age EMAIL: NTPRINTF@GMAIL.COM, Copyright (c) 2013 expert-programming-tutor.com. Python Python Class "blueprint"" The downside of that is, that now everything would be loaded at, # The implementation of a lazy-loading module in this file replaces the, # werkzeug package when imported from within. print("Hello my name is " + self.name), p1 = Person("John", 36) Donations to freeCodeCamp go toward our education initiatives, and help pay for servers, services, and staff. Working in agile, entrepreneurial, high paced global company. Cannot retrieve contributors at this time. We can use an if __name__ == "__main__" block to allow or prevent parts of code from being run when the modules are imported. Modify file_two to look like this: And to import the specific functions from the module, use the from import block in the file_one file: There is a really nice use case for the __name__ variable, whether you want a file that can be run as the main program or imported by other modules. One of those variables is called __name__. Get started, freeCodeCamp is a donor-supported tax-exempt 501(c)(3) nonprofit organization (United States Federal Tax Identification Number: 82-0779546). # import mapping to objects in other modules, # modules that should be imported when accessed as attributes of werkzeug, """Automatically import objects from the modules. p1 40, class Person: mysillyobject abc self, class Person: def __init__(self, name, age): :license: BSD, see LICENSE for more details. We also have thousands of freeCodeCamp study groups around the world. https://www.w3schools.com/python/python_classes.asp, 085-350-7540 (DTAC)
When the Python interpreter reads a file, the __name__ variable is set as __main__ if the module being run, or as the module's name if it is imported. When a Python interpreter reads a Python file, it first sets a few special variables. print(p1.age), Modify Object Properties self.age = age
class class pass Error print(p1.x), __init __ () self.name = name self.age = age, def myfunc(self): Create a Python module named file_one.py and paste this top level code inside: By running this file you will see exactly what we were talking about. Check out more articles like this on my freeCodeCamp profile, Medium profile, and other fun stuff I build on my GitHub page. print(p1.age) The self Parameter
class Learn to code for free.
Our mission: to help people learn to code for free. 084-88-00-255 (AIS) Then it executes the code from the file.
def myfunc(self):
Expert Programming Tutor Class and Objects Usually set automatically by a script. p1 = Person("John", 36) So when the interpreter runs a module, the __name__ variable will be set as __main__ if the module that is being run is the main program. , class Person: