+def _pos_int(s):
+ num = int(s)
+ if num < 0:
+ raise ValueError("can't accept negative value: %s" % (num,))
+ return num
+
+retry_opt = argparse.ArgumentParser(add_help=False)
+retry_opt.add_argument('--retries', type=_pos_int, default=3, help="""
+Maximum number of times to retry server requests that encounter temporary
+failures (e.g., server down). Default 3.""")
+