As an example of the use of Python and pyCGNS, suppose you needed to use a structured-grid CGNS file with an application that required an unstructured grid. This diagram illustrates how this could be done.

On the right is an end-user Python script. It would use pyCGNS to read the structured-grid CGNS file, and create an in-memory unstructured version of it as a Python/CGNS tree. The application code would then use the in-memory unstructured tree.