I'm missing something with protobuffers. Here is some questions that I have that I'm having difficulties answering. 

Is a .proto file enough to have get all the data out of? In the address book example that is on the site they seem to write the data out to a file and consume it out of a file (separate than the .proto file itself). I understand that the proto serializes the object structure and I know that it can serialize a message however I'm having a hard time finding where to put the data and retrieve within one contained .proto file itself. 
If question above is answered as I think it would my assumption is that one team can create the proto file and serialize the data with with java and another team can simply take the file and use python to deserialze it is that correct assumption?
Is a .proto file enough to have get all the data out of? 

The proto file is used to define the structure of the message. Each field is given a tag number. As long as you have the right proto file, the data can be de-serialized correctly. Yes the proto file will suffice.

one team can create the proto file and serialize the data with with
  java and another team can simply take the file and use python to
  deserialze it is that correct assumption?

One team can create the structure needed to define the data being sent / received and others can use that definition to communicate. As long as both teams use the same .proto file and the tag numbers are assigned correctly, you should have no trouble doing what you're asking.
Please help me understand protocol buffers