@Override
        public Object substitute(Map<String, String> context, Properties substitution) {
            String substituted = super.substitute(context, substitution).toString();
            return Tensor.from(type, substituted);
        }
A substitute string that should become a tensor once the substitution is performed at lookup time.
This is to support substitution strings in tensor values by parsing (only) such tensors at
lookup time rather than at construction time.
container-search/src/main/java/com/yahoo/search/query/profile/types/TensorFieldType.java