I'm using Google Base API for python to insert data in Google Merchant centre. The code is working fine till I asked for inserting the data (the last 3 lines of the code). Can anybody help me to figure out where the error can be.

import gdata.base.service
import gdata.service
import atom 
import gdata.base
gb_client = gdata.base.service.GBaseService() 
gb_client.email = raw_input('Please enter your username: ') 
gb_client.password = raw_input('Please enter your password: ')
print 'Logged in' 
item = gdata.base.GBaseItem() 
item.title = atom.Title(text='Cobra S2 Offset') 
item.link.append(atom.Link(rel='alternate', link_type='text/html',     
item.label.append(gdata.base.Label(text='Golf Driver')) 
item.item_type = gdata.base.ItemType(text='products') 
item.AddItemAttribute(name='Cobra S2 Offset', value='1') 
result = gb_client.InsertItem("Cobra S2 Offset")
insertion_time = result.published.text
my_entry_id = result.id.text

I just want to add that I'm getting 404 error.The error is coming once I'm including 18 onwards.