Imports of package api

PathSynopsis
contextPackage context defines the Context type, which carries deadlines, cancellation signals, and other request-scoped values across API boundaries and between processes.
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
mathPackage math provides basic constants and mathematical functions.
reflectPackage reflect implements run-time reflection, allowing a program to manipulate objects with arbitrary types.