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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 in_query(expression):
 """Match any of the values that exist in an array specified in query."""

    def _in(index, expression=expression):
        """Return store key for documents that satisfy expression."""
        ev = expression() if callable(expression) else expression
        try:
            iter(ev)
        except TypeError:
            raise AttributeError('$in argument must be an iterable!')
        hashed_ev = [index.get_hash_for(v) for v in ev]
        store_keys = set()

        for value in hashed_ev:
            store_keys |= set(index.get_keys_for(value))

        return list(store_keys)

    return _in