Admin CLI gives SyntaxWarning

[shuklanirdesh82]

PR #1165 introduces this regression.

Any admin cli commands gives following error message.

[root@sc2-rdops-vm02-dhcp-67-35:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py volume ls
/usr/lib/vmware/vmdkops/Python/vmdk_utils.py:79: SyntaxWarning: name 'datastores' is used prior to global declaration
  global datastores

Admin CLI version information.

[root@sc2-rdops-vm02-dhcp-67-35:~] /usr/lib/vmware/vmdkops/bin/vmdkops_admin.py status
/usr/lib/vmware/vmdkops/Python/vmdk_utils.py:79: SyntaxWarning: name 'datastores' is used prior to global declaration
  global datastores
=== Service: 
Version: 0.13.0ceef24-0.0.1 <<<<<< log information
Status: Running
Pid: 83518
Port: 1019
LogConfigFile: /etc/vmware/vmdkops/log_config.json
LogFile: /var/log/vmware/vmdk_ops.log
LogLevel: INFO
=== Authorization Config DB: 
DB_Mode: NotConfigured (no local DB, no symlink to shared DB)
DB_SharedLocation: N/A
DB_LocalPath: N/A