Yea, I just posted about old styles classes.

Does issubclass work recursively?
On Nov 10, 2013 2:55 PM, "Phillip Cloud" <notifications@github.com> wrote:

> In pandas/io/html.py:
>
> > @@ -665,10 +682,14 @@ def _print_as_set(s):
> >  def _validate_flavor(flavor):
> >      if flavor is None:
> >          flavor = 'lxml', 'bs4'
> > -    elif isinstance(flavor, string_types):
> > +    elif (isinstance(flavor, string_types))\
> > +        or (type(flavor) is type and Flavor in flavor.__bases__):
>
> Couple of things
>
> isinstance(flavor, type) is incorrect, my bad. But so is checking for type(flavor)
> is type since in Python 2 not all classes are instances of type they are
> their own classobj type.
>
> No need to worry about what subclassing type entails, just do this:
>
> issubclass(flavor, Flavor)
>
> —
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> .
>