code: static Schema createPersonSchema() {
          List<Field> fields = new ArrayList<Field>();
          fields.add(new Field("id", Schema.create(Type.INT), null, null));
          fields.add(new Field("age", Schema.create(Type.INT), null, null));
          fields.add(new Field("fname", Schema.create(Type.STRING), null, null));
          fields.add(new Field("lname", Schema.create(Type.STRING), null, null));
          
          Schema schema = Schema.createRecord("Person", null, "avro.test", false);
          schema.setFields(fields);
          
          return schema;
      }
docs: Creates the Avro schema for the Person store.