| bufio | Package bufio implements buffered I/O. | 
    | bytes | Package bytes implements functions for the manipulation of byte slices. | 
    | encoding/json | Package json implements encoding and decoding of JSON objects as defined in RFC 4627. | 
    | encoding/xml | Package xml implements a simple XML 1.0 parser that understands XML name spaces. | 
    | errors | Package errors implements functions to manipulate errors. | 
    | flag | Package flag implements command-line flag parsing. | 
    | fmt | Package fmt implements formatted I/O with functions analogous to C's printf and scanf. | 
    | golang.org/x/tools/go/vcs |  | 
    | io | Package io provides basic interfaces to I/O primitives. | 
    | io/ioutil | Package ioutil implements some I/O utility functions. | 
    | log | Package log implements a simple logging package. | 
    | net | Package net provides a portable interface for network I/O, including TCP/IP, UDP, domain name resolution, and Unix domain sockets. | 
    | net/http | Package http provides HTTP client and server implementations. | 
    | net/url | Package url parses URLs and implements query escaping. | 
    | os | Package os provides a platform-independent interface to operating system functionality. | 
    | os/exec | Package exec runs external commands. | 
    | path/filepath | Package filepath implements utility routines for manipulating filename paths in a way compatible with the target operating system-defined file paths. | 
    | regexp | Package regexp implements regular expression search. | 
    | runtime | Package runtime contains operations that interact with Go's runtime system, such as functions to control goroutines. | 
    | 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. | 
    | syscall | Package syscall contains an interface to the low-level operating system primitives. | 
    | time | Package time provides functionality for measuring and displaying time. |