FYI I am aware that one could define default values for any field through the developer mode User Interface.
I would like though to define my default values on my custom module. For the partner object specifically, I presume the way to go is something like:
from openerp.osv import orm, fields
class MyModule(orm.Model):
    _inherit = 'res.partner'
   _defaults = {
       # Not quite sure how to set the default value for country here.
   }
