Is Declaring Instance Variables as None in Python Good Practice?

python

Consider the following class:

class Person:
    def __init__(self, name, age):
        self.name = name
        self.age = age

My coworkers tend to define it like this:

class Person:
    name = None
    age = None

    def __init__(self, name, age):
        self.name = name
        self.age = age

The main reason for this is that their IDE of choice shows the properties for autocompletion.

Personally, I dislike the latter one, because it makes no sense that a class has those properties set to None.

Which one would be better practice and for what reasons?

Best Answer

I call the latter bad practice under the "this does not do what you think it does" rule.

Your coworker's position can be rewritten as: "I am going to create a bunch of class-static quasi-global variables which are never accessed, but which do take up space in the various class's namespace tables (__dict__), just to make my IDE do something."

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