{"id":151,"date":"2024-01-25T13:49:09","date_gmt":"2024-01-25T13:49:09","guid":{"rendered":"https:\/\/learnpython.elegantwallp.com\/?p=151"},"modified":"2024-01-25T13:49:25","modified_gmt":"2024-01-25T13:49:25","slug":"python-__str__","status":"publish","type":"post","link":"https:\/\/learnpython.elegantwallp.com\/2024\/01\/25\/python-__str__\/","title":{"rendered":"Python __str__"},"content":{"rendered":"\n

Summary<\/strong>: in this tutorial, you\u2019ll learn how to use the Python __str__<\/code> method to make a string representation of a class.<\/p>\n\n\n\n

Introduction to the Python __str__<\/code> method<\/h2>\n\n\n\n

Let\u2019s start with the\u00a0Person<\/code>\u00a0class:<\/p>\n\n\n\n

class Person: def __init__(self, first_name, last_name, age): self.first_name = first_name self.last_name = last_name self.age = age<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
The\u00a0Person<\/code>\u00a0class has three\u00a0instance attributes\u00a0including\u00a0first_name<\/code>,\u00a0last_name<\/code>, and\u00a0age<\/code>.<\/p>\n\n\n\n
The following creates a new instance of the\u00a0Person<\/code>\u00a0class and display it:<\/p>\n\n\n\n
person = Person('John', 'Doe', 25) print(person)<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Output:<\/p>\n\n\n\n
<__main__.Person object at 0x0000023CA16D13A0><\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
When you use the print()<\/code> function to display the instance of the Person<\/code> class, the print()<\/code> function shows the memory address of that instance.<\/p>\n\n\n\n
Sometimes, it\u2019s useful to have a string representation of an instance of a class. To customize the string representation of a class instance, the class needs to implement the __str__<\/code> magic method.<\/p>\n\n\n\n
Internally, Python will call the __str__<\/code> method automatically when an instance calls the str()<\/code> method.<\/p>\n\n\n\n
Note that the print()<\/code> function converts all non-keyword arguments to strings by passing them to the str()<\/code> before displaying the string values.<\/p>\n\n\n\n
The following illustrates how to implement the\u00a0__str__<\/code>\u00a0method in the\u00a0Person<\/code>\u00a0class:<\/p>\n\n\n\n
class Person: def __init__(self, first_name, last_name, age): self.first_name = first_name self.last_name = last_name self.age = age def __str__(self): return f'Person({self.first_name},{self.last_name},{self.age})'<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
And when you use the\u00a0print()<\/code>\u00a0function to print out an instance of the\u00a0Person<\/code>\u00a0class, Python calls the\u00a0__str__<\/code>\u00a0method defined in the\u00a0Person<\/code>\u00a0class. For example:<\/p>\n\n\n\n
person = Person('John', 'Doe', 25) print(person)<\/code>Code language: Python (python)<\/small><\/code><\/pre>\n\n\n\n
Output:<\/p>\n\n\n\n
Person(John,Doe,25)<\/code><\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"
Summary: in this tutorial, you\u2019ll learn how to use the Python __str__ method to make a string representation of a class. Introduction to the Python __str__ method Let\u2019s start with the\u00a0Person\u00a0class: The\u00a0Person\u00a0class has three\u00a0instance attributes\u00a0including\u00a0first_name,\u00a0last_name, and\u00a0age. The following creates a new instance of the\u00a0Person\u00a0class and display it: Output: When you use the print() function to display the instance of the Person class, the print() function […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[26],"tags":[],"class_list":["post-151","post","type-post","status-publish","format-standard","hentry","category-2-special-methods"],"_links":{"self":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/151","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/comments?post=151"}],"version-history":[{"count":1,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/151\/revisions"}],"predecessor-version":[{"id":152,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/posts\/151\/revisions\/152"}],"wp:attachment":[{"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/media?parent=151"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/categories?post=151"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/learnpython.elegantwallp.com\/wp-json\/wp\/v2\/tags?post=151"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}