failed to build reference: go build failed: exit status 1
cannot find package "1000-1999/1900-1999/1900-1909/1903/1903B.go" in any of:
	/usr/local/go/src/1000-1999/1900-1999/1900-1909/1903/1903B.go (from $GOROOT)
	/go/src/1000-1999/1900-1999/1900-1909/1903/1903B.go (from $GOPATH)