Python tutorial code snippet updates.

tutorials/06_python_support.md

@@ -261,10 +261,9 @@ We can declare the throttling option using the following code :
  # Setting the throttling option
  opts = AdvertiseMessageOptions()
  opts.msgs_per_sec = 1
- pub = node.advertise(topic_name, StringMsg, opts);
- if (!pub):
+ pub = node.advertise(topic_name, StringMsg, opts)
+ if not pub:
  print("Error advertising topic" + topic_name)
- return False
 ```
 
 ### Walkthrough
@@ -280,7 +279,7 @@ it to set the publishing rate (the member `msgs_per_sec`), In our case, the rate
 specified is 1 msg/sec.
 
 ```{.py}
- pub = node.advertise(topic_name, StringMsg, opts);
+ pub = node.advertise(topic_name, StringMsg, opts)
 ```
 
 Next, we advertise the topic with message throttling enabled. To do it, we pass opts
@@ -341,8 +340,8 @@ We can declare the topic remapping option using the following code:
 
  # Create a transport node and remap a topic.
  nodeOpts = NodeOptions()
- nodeOptions.add_topic_remap("/foo", "/bar");
- node = Node(nodeOptions);
+ nodeOpts.add_topic_remap("/foo", "/bar")
+ node = Node(nodeOpts)
 ```
 
 You can modify the publisher example to add this option.