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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def setup(self, **kwargs):
 """ Setting up Grab instance configuration. """


        for key in kwargs:
            if key not in self.config.keys():
                raise error.GrabMisuseError('Unknown option: %s' % key)

        if 'url' in kwargs:
            if self.config.get('url'):
                kwargs['url'] = self.make_url_absolute(kwargs['url'])
        self.config.update(kwargs)