Underscore vs Double underscore with variables and methods

Question

Can someone please explain the exact meaning of having leading underscores before an object's name in Python?

Sagar Pardeshi · Answer

Hi Dipa, follow the very simple definition Single underscore It is used before an object’s name to indicate other programmers that the method is meant to be private. It is also used in the name of methods which are fully intended to be overridden by subclasses. Ex- _abc Double underscore They are used for fully private methods. Ex- if your class is intended to be subclassed and you have attributes which you do not want the subclass to use, you can name them using a double underscore. The rules of underscores in Python remain the same whether it is an object or a function, etc. Let us see an example of class for better understanding of the difference between the single and double underscores. _single_leading_underscore : weak "internal use" indicator. E.g. from M import * does not import objects whose name starts with an underscore. single_trailing_underscore_ : used by convention to avoid conflicts with Python keyword, e.g. Tkinter.Toplevel(master, class_='ClassName') __double_leading_underscore : when naming a class attribute, invokes name mangling (inside class FooBar, __boo becomes _FooBar__boo; see below). __double_leading_and_trailing_underscore__ : "magic" objects or attributes that live in user-controlled namespaces. E.g. __init__, __import__ or __file__. Never invent such names; only use them as documented.

Dinesh Gabhane · Answer

nicely explained here https://stackoverflow.com/questions/1301346/what-is-the-meaning-of-a-single-and-a-double-underscore-before-an-object-name https://dbader.org/blog/meaning-of-underscores-in-python

Sagar Lad · Answer

https://dbader.org/blog/meaning-of-underscores-in-python

Dipa Mehta · Answer

Thanks for the links and the best explaination. I'll apply these in my further next snippets.

Underscore vs Double underscore with variables and methods

Answers (4)