def Run(self, args):
    """Run."""
    time_start = time.time()

    args.python_code.Verify(
        config.CONFIG["Client.executable_signing_public_key"])

    # The execed code can assign to this variable if it wants to return data.
    logging.debug("exec for python code %s", args.python_code.data[0:100])

    context = globals().copy()
    context["py_args"] = args.py_args.ToDict()
    context["magic_return_str"] = ""
    # Export the Progress function to allow python hacks to call it.
    context["Progress"] = self.Progress

    stdout = io.StringIO()
    with utils.Stubber(sys, "stdout", StdOutHook(stdout)):
      exec(args.python_code.data, context)  # pylint: disable=exec-used

    stdout_output = stdout.getvalue()
    magic_str_output = context.get("magic_return_str")

    if stdout_output and magic_str_output:
      output = "Stdout: %s\nMagic Str:%s\n" % (stdout_output, magic_str_output)
    else:
      output = stdout_output or magic_str_output

    time_used = time.time() - time_start
    # We have to return microseconds.
    self.SendReply(
        rdf_client_action.ExecutePythonResponse(
            time_used=int(1e6 * time_used), return_val=output))