Imports of package defaultcheck

PathSynopsis
fmtPackage fmt implements formatted I/O with functions analogous to C's printf and scanf.
github.com/gogo/protobuf/gogoprotoPackage gogoproto provides extensions for protocol buffers to achieve:
github.com/gogo/protobuf/protoc-gen-gogo/generatorThe code generator for the plugin for the Google protocol buffer compiler.
osPackage os provides a platform-independent interface to operating system functionality.