Help needed: dynamically pull data from different levels of a dict

[Peter Rubenstein]

--Reposting in plan text, apologies--

Hi,

I'd appreciate a bit of help on this problem.  I have some data that I've converted to a dict and I want to pull out individual pieces of it.

Simplified version--
a={'1':'a', '2':'b', '3':{4:'d'}, '5':{'6': {'7': [ {'8':'e'}, {'9':'f'} ] } } }

I'd like to be able to code something like:

data_needed = ['1', '2', '3:4', '5:6:7-8']for val in data_needed:        answer=extract_from(a,val)        print answer

And get:abcde

Problem is I can't figure out what extract_from would look like, such that it would proceed dynamically down to the right level.  I'm open to the possibility that I'm not approaching this the right way.
If it helps, one member of my actual dict quoted below.  So in real life, something likedata_needed=['name','active-defects', 'admin-status:format', 'description', 'traffic-statistics:input-bps']etc.

Thanks in advance,Peter

{ 'ge-0/0/0': {'active-alarms': {'interface-alarms': {'alarm-not-present': ''}},  'active-defects': {'interface-alarms': {'alarm-not-present': ''}},  'admin-status': {'_text': 'up', 'format': 'Enabled'},  'current-physical-address': '00:1f:12:c0:e8:00',  'description': 'INFRA:CROSS:ASH-64CB-1B:GE-0/0/0:',  'hardware-physical-address': '00:1f:12:c0:e8:00',  'if-config-flags': {'iff-snmp-traps': '', 'internal-flags': '0x4000'},  'if-device-flags': {'ifdf-present': '', 'ifdf-running': ''},  'if-flow-control': 'enabled',  'if-media-flags': {'ifmf-none': ''},  'interface-flapped': {'_text': '2010-05-23 18:20:36 UTC (92w3d 02:27 ago)',   'seconds': '55909644'},  'l2pt-error': 'none',  'link-level-type': 'Ethernet',  'local-index': '171',  'logical-interface': {'address-family': [{'address-family-flags': {'ifff-no-redirects': '',      'internal-flags': '0x0'},     'address-family-name': 'inet',     'interface-address': {'ifa-destination': '207.46.43.2/31',      'ifa-flags': {'ifaf-current-preferred': '', 'ifaf-current-primary': ''},      'ifa-local': '207.46.43.2'},     'mtu': '9178'},    {'address-family-flags': {'ifff-mtu-user-conf': '',      'internal-flags': '0x10000000'},     'address-family-name': 'mpls',     'mtu': '9174'},    {'address-family-flags': {'ifff-none': ''},     'address-family-name': 'multiservice',     'mtu': 'Unlimited'}],   'description': 'INFRA:CROSS:ASH-64CB-1B:GE-0/0/0.0:',   'encapsulation': 'ENET2',   'if-config-flags': {'iff-snmp-traps': ''},   'local-index': '67',   'name': 'ge-0/0/0.0',   'snmp-index': '117',   'traffic-statistics': {'input-packets': '46367422526659',    'output-packets': '35670513402384',    'style': 'brief'}},  'loopback': 'disabled',  'mtu': '9192',  'name': 'ge-0/0/0',  'oper-status': 'up',  'physical-interface-cos-information': {'physical-interface-cos-hw-max-queues': '8',   'physical-interface-cos-use-max-queues': '8'},  'snmp-index': '116',  'source-filtering': 'disabled',  'speed': '10Gbps',  'traffic-statistics': {'input-bps': '4104358720',   'input-pps': '1059450',   'output-bps': '2323588888',   'output-pps': '537816',   'style': 'brief'}},}