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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 _update_metadata(self, kwargs=None):
        '''Extract any additional attributes to hold with the instance
           from kwargs
        '''

        # If not given metadata, use instance.list to get it for container
        if kwargs == None and hasattr(self, 'name'):
            kwargs = self._list(self.name, quiet=True, return_json=True)

        # Add acceptable arguments
        for arg in ['pid', 'name']:

           # Skip over non-iterables:
           if arg in kwargs:
               setattr(self, arg, kwargs[arg])
       
        if "image" in kwargs:
            self._image = kwargs['image']
        elif "container_image" in kwargs:
            self._image = kwargs['container_image']