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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(self, *args, **kwargs):
        '''Preserves order if given an assoc list.
        '''
        arg = dict_arg(*args, **kwargs)
        if isinstance(arg, list):
          for key, val in arg:
              self[key] = val
        else:
            super(AssocDict, self).update(arg)