private TensorAddress consumeLabels() {
            TensorAddress.Builder addressBuilder = new TensorAddress.Builder(builder.type());
            if ( ! consumeOptional('{')) return addressBuilder.build();
            while ( ! consumeOptional('}')) {
                String dimension = consumeIdentifier();
                consume(':');
                String label = consumeLabel();
                addressBuilder.add(dimension, label);
                consumeOptional(',');
            }
            return addressBuilder.build();
        }
Creates a tensor address from a string on the form {dimension1:label1,dimension2:label2,...}
vespajlib/src/main/java/com/yahoo/tensor/TensorParser.java