Fix conversion from Python dict to arrow type in ROS2 example

examples/python-ros2-dataflow/random_turtle.py

@@ -51,19 +51,8 @@ for i in range(500):
                                 },
                             }
 
-                            print(direction, flush=True)
-                            # TODO FIXME: The below line seems to result in an
-                            # `["linear", "angular"]` array, completely ignoring the values.
-                            direction_arrow = pa.array(
-                                direction,
-                                # TODO: maybe type annotations help somehow?
-                                # type=pa.map_(
-                                #     pa.utf8(),
-                                #     pa.map_(pa.utf8(), pa.float32()),
-                                # ),
-                            )
-                            print(direction_arrow, flush=True)
-                            # twist_writer.publish(direction_arrow)
+                            direction_arrow = pa.array([pa.scalar(direction)])
+                            twist_writer.publish(direction_arrow)
                         case "tick":
                             pass