Blender's Console can provide valuable information during script execution. When writing Python scripts using Blender API, the Console becomes your friend. The Console is a text only display - a separate window. Simple print()statements will typically display on the Console. These print()statements are used to provide status of a script's processing. So where is the Console?
Windows: Blender provides access from it's own menu item: Window:Toggle System Console. Be sure to Toggle the Console 'on' before running a script. You can not toggle the Console during script execution
Mac OS: The app named Console typically has too much traffic being routed to it, so alternate methods provide much better performance for a specific task such as writing Blender scripts. Alternate methods mean a few more steps. Use the Terminal app instead of Console. However, Terminal needs to be connected to Blender for the communication to take place. To make this connection we will create a shell command. In a text editor, paste these lines:
Save the file as:
You can replace the 'blender_start' segment of the filename with words of your own choosing, however, the '.command' part is a must. When this file is executed, it will launch Blender and Terminal with a connection between the two. I placed my .command file on the desktop which allows me to double click it at any time to run Blender.