mongodb FindAndModify - update data

I have this already in the MongoDB collections.

{ "_id" : ObjectId("4e677efce88c7f0718000000"), "ptbn" : "indl000000001", "tbucode" : "5649", "district" : "west", "dcode" : "110048", "tbu" : "super clinic", "state" : "开发者_开发百科delhi" }

I am unable to understand how to work with FindAndModify from MongoDb

I am working on MongoDb 1.8

I just want to modify the 'state' from delhi to goa, and 'district' from west to north.

How do I modify all entries EXCEPT 'ptbn' in Python-2.6

This is what I've tried so far:

     connection = Connection('localhost', 27017)
     db = connection.health
     tc = db.tc_basic

     basic = {'state' : state, 
              'district' : district,
              'Dcode' : Dcode, 
              'tbu' : tbu,
              'tbucode' : tbucode,
              'ptbn' : ptbn
              }

     tc.save(basic)

You don't actually need findAndModify for this. A simple update() will do the trick.

db.tc_basic.update({'_id':ObjectId("...")}, {'$set': {'state': 'goa', 'district': 'north'}})

For more details on what you can do with update() see: http://www.mongodb.org/display/DOCS/Updating