'Returns the value specified for option in style.
If state is specified it is expected to be a sequence of one
or more states. If the default argument is set, it is used as
a fallback value in case no specification for option is found.'

def lookup(self, style, option, state=None, default=None):

    state = ('    '.join(state) if state else '')
    return self.tk.call(self._name, 'lookup', style, ('-%s' % option), state, default)
