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Python Object-Oriented Python (retired) Inheritance Instance Methods

Chih-Wei Hsu
Chih-Wei Hsu
11,132 Points
Posted by Chih-Wei Hsu
Chih-Wei Hsu
11,132 Points

adding self before a variable name

i've noticed that when defining the get_weapon method, the variable name weapon_choice was not preceded with self. Do we only need to add self. for variables defined under the __init__ method ??

[MOD: added ` ` around __init__ -cf]

1 Answer

Chris Freeman
MOD
Chris Freeman
Treehouse Moderator 68,423 Points
Chris Freeman
Chris Freeman
Treehouse Moderator 68,423 Points

The self represents the instance of a class being referenced. If it is used as a prefix for a variable name, then the variable is an attribute (or method) of that instance. During __init__, instance attributes are being define, so self is needed. Attributes are persistent.

In other cases, if a variable is only being used as an method argument or a temporary variable within a method, it doesn't have the self. prefix and is a local variable. That is, it disappears after the method is finished (it is non-persistent).

Chih-Wei Hsu
Chih-Wei Hsu
11,132 Points
Chih-Wei Hsu
Chih-Wei Hsu
11,132 Points

thank you for the very clear explanation!