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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 count_vocab_items(self, counter: Dict[str, Dict[str, int]]):
 """ Increments counts in the given ``counter`` for all of the vocabulary items in all of the ``Fields`` in this ``Instance``. """

        for field in self.fields.values():
            field.count_vocab_items(counter)