# 5.14 `cmd` -- Support for line-oriented command interpreters

The `Cmd` class provides a simple framework for writing line-oriented command interpreters. These are often useful for test harnesses, administrative tools, and prototypes that will later be wrapped in a more sophisticated interface.

class `Cmd`([completekey])
  A `Cmd` instance or subclass instance is a line-oriented interpreter framework. There is no good reason to instantiate `Cmd` itself; rather, it's useful as a superclass of an interpreter class you define yourself in order to inherit `Cmd`'s methods and encapsulate action methods.

  The optional argument is the `readline` name of a completion key; it defaults to `Tab`. If completekey is not `None` and `readline` is available, command completion is done automatically.

Subsections

- 5.14.1 Cmd Objects