Sets the value of the argument with the specified id using the argument passed
        in from the shell session.

def _set_arg_generic(self, argid, arg, cast=str):
        """Sets the value of the argument with the specified id using the argument passed
        in from the shell session.
        """
        usable, filename, append = self._redirect_split(arg)
        if usable != "":
            self.curargs[argid] = cast(usable)
        if argid in self.curargs:
            result = "{}: '{}'".format(argid.upper(), self.curargs[argid])
            self._redirect_output(result, filename, append, msg.info)