| encoding/base64 | Package base64 implements base64 encoding as specified by RFC 4648. |
| errors | Package errors implements functions to manipulate errors. |
| github.com/golang/protobuf/proto | Package proto provides functionality for handling protocol buffer messages. |
| google.golang.org/appengine/datastore/internal/cloudpb | Package cloudpb is a subset of protobufs, copied from google.golang.org/genproto/googleapis/datastore/v1. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |