Building a Single Command Application
When building a command line tool, you may not need to provide several commands. In such case, having to pass the command name each time is tedious. Fortunately, it is possible to remove this need by using default() when adding a command:
from cleo import Application
command = GreetCommand()
app = Application()
app.add(command.default())
# this now executes the 'GreetCommand' without passing its name
app.run()