human
Solve the following python programming problem given the following code:
def add_client(self, base_client_instance) : 
    'Add a new instance of :class:`BaseClient` descendant.

        `self` will store a reference to `base_client_instance`.

        Example:

        >>> def test_clients():
        ...     from keystoneclient.auth import keystone
        ...     from openstack.common.apiclient import client
        ...     auth = keystone.KeystoneAuthPlugin(
        ...         username="user", password="pass", tenant_name="tenant",
        ...         auth_url="http://auth:5000/v2.0")
        ...     openstack_client = client.HTTPClient(auth)
        ...     # create nova client
        ...     from novaclient.v1_1 import client
        ...     client.Client(openstack_client)
        ...     # create keystone client
        ...     from keystoneclient.v2_0 import client
        ...     client.Client(openstack_client)
        ...     # use them
        ...     openstack_client.identity.tenants.list()
        ...     openstack_client.compute.servers.list()
        ' 
    service_type = service_type.service_type 
    if (service_type and (not hasattr (self, service_type))) : 
        setattr (self, service_type, base_client_instance) 

    
    

    Fix the buggy line: service_type = service_type.service_type
assistant
#Here is Python program to fix the buggy line: service_type = service_type.

service_type = base_client_instance.service_type