If you are using Chameleon to generate HL7 messages, you can create the following Python scripts:

• The Global Outbound Preprocess Script, which is executed before message generation to define variables and functions;
• The Table Outbound Scripts, which manipulate table column data;
• The Segment Outbound Scripts, which manipulate segment field data;
• The Global Outbound Post Process Script, which is executed after the message string has been generated.

	Iguana Users If you are using Iguana to develop your application, you need Chameleon to create the Message Definition File (VMD) file that handles HL7 message generation. You can use the Python scripts described in this section to edit the message data that is being generated.

Here is a diagram that shows the order in which these scripts are executed:

The following sections describe these scripts in more detail.