| errors | Package errors implements functions to manipulate errors. |
| fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. |
| golang.org/x/text/internal | Package internal contains non-exported functionality that are used by packages in the text repository. |
| golang.org/x/text/internal/catmsg | Package catmsg contains support types for package x/text/message/catalog. |
| golang.org/x/text/language | Package language implements BCP 47 language tags and related functionality. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |