Run the command line tool.

def _call_cmd_line(self):
        """Run the command line tool."""
        try:
            logging.info("Calling Popen with: {}".format(self.args))
            p = Popen(self.args, stdin=PIPE, stdout=PIPE, stderr=PIPE)
        except OSError:
            raise(RuntimeError("No such command found in PATH"))

        # Calling this command with newline as stdin as the
        # iCommnads hangs waiting for user input if the password
        # has not been set or has timed out.
        self.stdout, self.stderr = p.communicate("\n".encode())
        self.stdout = self.stdout.decode("utf-8")
        self.stderr = self.stderr.decode("utf-8")
        self.returncode = p.returncode