Instead of exposing each method of an object, this metaclass exposes all object methods that don't start with a '_' character.

import types
class exposed(type):
   def __init__(cls, name, bases, dict):
      super(exposed, cls).__init__(name, bases, dict)
      for name, value in dict.iteritems():
        if type(value)==types.FunctionType and not name.startswith('_'):
           value.exposed = True

Usage:

class MyClass:
   __metaclass__ = exposed
   def hello(self): 
      return 'This is exposed!'