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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def main(self, argv=None, exit=True):
 """ Shortcut to prepare a bowl of guacamole and eat it. :param argv: Command line arguments or None. None means that sys.argv is used :param exit: Raise SystemExit after finishing execution :returns: Whatever is returned by the eating the guacamole. :raises: Whatever is raised by eating the guacamole. .. note:: This method always either raises and exception or returns an object. The way it behaves depends on the value of the `exit` argument. This method can be used to quickly take a recipe, prepare the guacamole and eat it. It is named main as it is applicable as the main method of an application. The `exit` argument controls if main returns normally or raises SystemExit. By default it will raise SystemExit (it will either wrap the return value with SystemExit or re-raise the SystemExit exception again). If SystemExit is raised but `exit` is False the argument to SystemExit is unwrapped and returned instead. """

        bowl = self.prepare()
        try:
            retval = bowl.eat(argv)
        except SystemExit as exc:
            if exit:
                raise
            else:
                return exc.args[0]
        else:
            if retval is None:
                retval = 0
            if exit:
                raise SystemExit(retval)
            else:
                return retval