code: def get_doc(doc_id, db_name, server_url='http://127.0.0.1:5984/', rev=None):
      
      db = get_server(server_url)[db_name]
      if rev:
          headers, response = db.resource.get(doc_id, rev=rev)
          return couchdb.client.Document(response)
      return db[doc_id]
docs: Return a CouchDB document, given its ID, revision and database name.