Python 3 compatibility: updated iteritems to items.

[r-2st]

While trying to bring up the environment ../templates/etc/frr/frr.conf.j2 & ../templates/etc/frr/zebra.conf.j2 errored out with:

fatal: [spine1]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [spine2]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [leaf1]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [leaf2]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [leaf3]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [leaf4]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [compute1]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}
fatal: [compute2]: FAILED! => {"changed": false, "msg": "AnsibleUndefinedVariable: 'dict object' has no attribute 'iteritems'"}

After doing some digging it was due to my installed version of ansible using python3:

>  ansible --version
ansible 2.9.2
  config file = None
  configured module search path = ['/Users/ross.thompson/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/local/lib/python3.7/site-packages/ansible
  executable location = /usr/local/bin/ansible
  python version = 3.7.7 (default, Mar 10 2020, 15:43:33) [Clang 11.0.0 (clang-1100.0.33.17)]

In the template files iteritems was changed to items for python3 compatibility. After that the environment was able to launch without issue:

PLAY RECAP *********************************************************************
compute1                   : ok=53   changed=20   unreachable=0    failed=0    skipped=44   rescued=0    ignored=0
compute2                   : ok=53   changed=20   unreachable=0    failed=0    skipped=44   rescued=0    ignored=0
leaf1                      : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0
leaf2                      : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0
leaf3                      : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0
leaf4                      : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0
spine1                     : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0
spine2                     : ok=34   changed=11   unreachable=0    failed=0    skipped=18   rescued=0    ignored=0

Did a quick test to confirm python2 backwards compatibility to make sure this change would not break things:

Python 2.7.17 (default, Dec 23 2019, 21:25:33)
[GCC 4.2.1 Compatible Apple LLVM 11.0.0 (clang-1100.0.33.16)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> d={1:'one',2:'two',3:'three'}
>>> print 'd.items():'
d.items():
>>> for k,v in d.items():
...    if d[k] is v: print '\tthey are the same object'
...    else: print '\tthey are different'
...
	they are the same object
	they are the same object
	they are the same object
>>> print 'd.iteritems():'
d.iteritems():
>>> for k,v in d.iteritems():
...    if d[k] is v: print '\tthey are the same object'
...    else: print '\tthey are different'
...
	they are the same object
	they are the same object
	they are the same object
>>> quit()

Please let me know if there are any points that were missed and ill be happy to look into them.
-Ross