Python Script Tools are added to standard toolboxes (*.tbx) of ArcGIS for Desktop

Python Script Tools are added to standard toolboxes (.tbx) of ArcGIS for Desktop and should not be confused with Python Toolboxes (.pyt) which have only been available since ArcGIS 10.1 for Desktop and are written entirely in Python.

Python Script Tools have a tool dialog that is configured via its Properties and NOT within code.

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