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Getting attributes of a class

I want to get the attributes of a class, say:

class MyClass():
  a = "12"
  b = "34"

  def myfunc(self):
    return self.a

using MyClass.__dict__ gives me a list of attributes and functions, and even functions like __module__ and __doc__. While MyClass().__dict__ gives me an empty dict unless I explicitly set an attribute value of that instance.

I just want the attributes, in the example above those would be: a and b


  • Try the inspect module. getmembers and the various tests should be helpful.


    For example,

    class MyClass(object):
        a = '12'
        b = '34'
        def myfunc(self):
            return self.a
    >>> import inspect
    >>> inspect.getmembers(MyClass, lambda a:not(inspect.isroutine(a)))
    [('__class__', type),
      <dictproxy {'__dict__': <attribute '__dict__' of 'MyClass' objects>,
       '__doc__': None,
       '__module__': '__main__',
       '__weakref__': <attribute '__weakref__' of 'MyClass' objects>,
       'a': '34',
       'b': '12',
       'myfunc': <function __main__.myfunc>}>),
     ('__doc__', None),
     ('__module__', '__main__'),
     ('__weakref__', <attribute '__weakref__' of 'MyClass' objects>),
     ('a', '34'),
     ('b', '12')]

    Now, the special methods and attributes get on my nerves- those can be dealt with in a number of ways, the easiest of which is just to filter based on name.

    >>> attributes = inspect.getmembers(MyClass, lambda a:not(inspect.isroutine(a)))
    >>> [a for a in attributes if not(a[0].startswith('__') and a[0].endswith('__'))]
    [('a', '34'), ('b', '12')]

    ...and the more complicated of which can include special attribute name checks or even metaclasses ;)