class cmd.Cmd(completekey='tab', stdin=None, stdout=None)
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 completekey is the readline name of a completion key; it defaults to Tab. If completekey is not None and readline is available, command compl