NameError in Python when listing static attributes from within same class

Question

I have the following python class:

class list_stuff:    
        A = 'a'
        B = 'b'
        C = 'c'
        stufflist = [v for k,v in list_stuff.__dict__.items() if not k.startswith("__")]

But it shows a NameError saying undefined variable list_stuff.

According to this, it should work.

I also tried with:

list_stuff().__dict__.items()

But still same error. What am I missing here?

Try this: https://stackoverflow.com/questions/9058305/getting-attributes-of-a-class — Jean-François Fabre, Nov 03 '17 at 19:02

score 1 · Answer 1 · answered Nov 03 '17 at 19:17

1

In Python you cannot reference the class in the class body. The issue I see here is that you are referring to the class list_stuff within the class definition. To resolve simply move that line outside the class:

class list_stuff:    
    A = 'a'
    B = 'b'
    C = 'c'

stufflist = [v for k,v in list_stuff.__dict__.items() if not k.startswith("__")]

Here is the documentation on classes

answered Nov 03 '17 at 19:17

Cyzanfar

6,997
9
43
81

That works. But I wanted to keep it inside the class, so i ended up using a @classmethod, then referenced the classname with cls.list_stuff. This gives me the same effect I wanted originally. – EricBlair1984 Nov 03 '17 at 19:22
That’s true you could do it achieve what you want that way! Happy to help :) – Cyzanfar Nov 03 '17 at 19:24

score 1 · Accepted Answer · answered Nov 03 '17 at 19:26

I ended up doing this:

class list_stuff:    
    A = 'a'
    B = 'b'
    C = 'c'

    @classmethod
    def stufflist(cls):
        return [v for k,v in cls.list_stuff.__dict__.items() if not k.startswith("__")]

which has the same effect as my original intent.

Thanks all for quick replies.

score 0 · Answer 3 · answered Nov 03 '17 at 19:14

0

The problem seems to be the indentation, as you are essentially calling the class from within.

Try this:

class list_stuff:    
    A = 'a'
    B = 'b'
    C = 'c'
stufflist = [v for k,v in list_stuff.__dict__.items() if not k.startswith("__")]

answered Nov 03 '17 at 19:14

leiberl

73
1
5

score 0 · Answer 4 · answered Nov 03 '17 at 19:31

You can create a method that would generate the list attribute you wish. First you will need to generate an instance of that class, before running the get_list() method.

class list_stuff():
    A = 'a'
    B = 'b'
    C = 'c'  

def get_list(self):
    self.thelist = [v for k,v in list_stuff.__dict__.items() if not k.startswith("__")]
    return self.thelist

list_a = list_stuff()
print list_a.get_list()
print list_a.thelistenter code here

This is what it returns:

['a', 'b', 'c', <function get_list at 0x7f07d6c63668>]
['a', 'b', 'c', <function get_list at 0x7f07d6c63668>]

NameError in Python when listing static attributes from within same class

4 Answers4