scripts: Replace optparse with argparse.

scripts/nagios/check-rabbitmq-consumers

@@ -2,7 +2,7 @@
 
 import sys
 import time
-import optparse
+import argparse
 from collections import defaultdict
 import os
 import subprocess
@@ -23,14 +23,14 @@ if 'USER' in os.environ and not os.environ['USER'] in ['root', 'rabbitmq']:
 
 usage = """Usage: check-rabbitmq-consumers --queue=[queue-name] --min-threshold=[min-threshold]"""
 
-parser = optparse.OptionParser(usage=usage)
-parser.add_option('--min-threshold',
-                  dest='min_count',
-                  type="int",
-                  default=1,
-                  action='store')
+parser = argparse.ArgumentParser(usage=usage)
+parser.add_argument('--min-threshold',
+                    dest='min_count',
+                    type=int,
+                    default=1,
+                    action='store')
 
-(options, args) = parser.parse_args()
+options = parser.parse_args()
 
 output = subprocess.check_output(['/usr/sbin/rabbitmqctl', 'list_consumers'],
                                  universal_newlines=True)