Example gdb command in python

a.out-gdb.py

print("Loaded python script!")

import gdb
class HelloWorldCommand (gdb.Command):
    "MyCommand! yay."

    def __init__ (self):
        super(HelloWorldCommand, self).__init__("helloworld", gdb.COMMAND_USER, gdb.COMPLETE_NONE, True)

    def invoke(self, arg, from_tty):
        print("Hello world")
        print(str(arg))
        print(str(from_tty))

HelloWorldCommand()