| 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/net/http/httpguts | Package httpguts provides functions implementing various details of the HTTP specification. |
| golang.org/x/net/http2/hpack | Package hpack implements HPACK, a compression format for efficiently representing HTTP header fields in the context of HTTP/2. |
| net/http | Package http provides HTTP client and server implementations. |
| net/http/httptrace | Package httptrace provides mechanisms to trace the events within HTTP client requests. |
| sort | Package sort provides primitives for sorting slices and user-defined collections. |
| strconv | Package strconv implements conversions to and from string representations of basic data types. |
| strings | Package strings implements simple functions to manipulate UTF-8 encoded strings. |
| sync | Package sync provides basic synchronization primitives such as mutual exclusion locks. |