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Andrés Muñoz
Asked: 2020-02-26 23:48:24 +0800 CST 2020-02-26 23:48:24 +0800 CST

What is the use and meaning of _name __name or __name__ in python?

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What is the meaning of; underscore, double underscore, etc? when naming objects in python?

python

2 Answers

    • _nombre(prefix with a single underscore): Indicates that the name is for internal use. When importing a module with from m import *, no names starting with _will be imported.

      It is also used in classes as a way to indicate that a certain method is for internal use and is not part of the public API, but this is convention and is not given any special meaning by the language.

    • __nombre(double underscore prefix, maximum one suffix underscore): Indicates that a certain member of a class is private, and converts the name via name mangling to _clase__nombre, where class is the name of the current class.

      The intent of name conversion is to avoid accidents, for example when inheriting from a class with "private" attributes or methods. It does not prevent in any case its overwriting or access in general.

    • __nombre__(prefix and suffix with double underscore): Indicates that it is a magic name . In general, these are either special variables or methods with a special meaning or behavior within the language. Never define your own magic names, just use them as documented .

    You can find these conventions in the PEP 8 .

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  2. Best Answer

    This is found in the documentation,

    Python: Naming Styles (English)

    Where what Darkhogg comments is described

    In addition, the following special forms with initial or final underscores are recognized (these can generally be combined with any convention):

    _single_leading_underscore : weak "internal use" indicator. For example: from M import *don't import objects whose name starts with an underscore.

    single_trailing_underscore_ : used by convention to avoid keyword conflicts Python, e.g.

     Tkinter.Toplevel(master, class_='ClassName')

    __double_leading_underscore : When naming a class attribute, invokes name renaming (inside the FooBar class, casts __booto _FooBar__boo;).

    __double_leading_and_trailing_underscore__ : "magic" objects or attributes that live in user controlled namespaces. For example: __init__, __import__or __file__. Never invent such names; only use them as documented.

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