Merge pull request #3129 from kefeimo/hot-fix/uuid-having-extr-chars

revivied Craig s code to resolved the issue that uuid has extra char when using vctl status

volttron/platform/control/control_utils.py

@@ -36,23 +36,20 @@
 # under Contract DE-AC05-76RL01830
 # }}}
 import collections
-import itertools
 import sys
 import re
 from volttron.platform import jsonapi
 from volttron.platform.agent.utils import is_secure_mode
+import os
 
 _stdout = sys.stdout
 _stderr = sys.stderr
 
 
 def _calc_min_uuid_length(agents):
-    n = 0
-    for agent1, agent2 in itertools.combinations(agents, 2):
-        common_len = sum(1 for a, b in zip(agent1.uuid, agent2.uuid) if a == b)
-        if common_len > n:
-            n = common_len
-    return n + 1
+    agent_ids = [agent.uuid for agent in agents]
+    common_len = len(os.path.commonprefix(agent_ids))
+    return common_len + 1
 
 
 def _list_agents(aip):