Python – Find static properties of a class in Python

This is an unusual question, but I’d like to dynamically generate the __slots__ properties of the class based on any properties I happen to add to the class.

For example, if I have a class:

class A(object):
    one = 1
    two = 2

__slots__ = ['one', 'two']

I

want to do this dynamically instead of specifying the parameters manually, how do I do that?

When you tried to define slot , the class had not yet been built, so you could not define it dynamically from class A.

To get the desired behavior, use metaclasses to reflect on the definition of A and add slot properties.

class MakeSlots(type):

def __new__(cls, name, bases, attrs):
        attrs['__slots__'] = attrs.keys()

return super(MakeSlots, cls).__new__(cls, name, bases, attrs)

class A(object):
    one = 1
    two = 2

__metaclass__ = MakeSlots