'Populates self._user_dn with the distinguished name of our user. This
will either construct the DN from a template in
AUTH_LDAP_USER_DN_TEMPLATE or connect to the server and search for it.'

def _load_user_dn(self):

    if self._using_simple_bind_mode():
        self._construct_simple_user_dn()
    else:
        self._search_for_user_dn()
