Get node objects from GCP.

def nodes_gcp(c_obj):
    """Get node objects from GCP."""
    gcp_nodes = []
    try:
        gcp_nodes = c_obj.list_nodes(ex_use_disk_cache=True)
    except BaseHTTPError as e:
        abort_err("\r HTTP Error with GCP: {}".format(e))
    gcp_nodes = adj_nodes_gcp(gcp_nodes)
    return gcp_nodes