GeezerVison

Create a class object dynamically using the appropriate metaclass.

Create a class object dynamically using the appropriate metaclass.

*name*, *bases*, and *kwds* are the class name, the base classes,
and the keywords of the equivalent class definition (such as
'metaclass').  *kwds* is not a namespace like the third argument
of type().  For example:

    new_class('Test', (A, B), {'metaclass': Meta, 'foo': 42})

is equivalent to:

    class Test(A, B, metaclass=Meta, foo=42):
        pass

To populate the namespace, pass *exec_body*, a callable that takes
the newly created dictionary and populates it.  For example:

    new_class('C', (MyABC,), {},
              exec_body=lambda ns: ns.update(namespace))