Imports github.com/emersion/go-mbox gonum.org/v1/gonum/graph gonum.org/v1/gonum/graph/encoding gonum.org/v1/gonum/graph/encoding/dot gonum.org/v1/gonum/graph/formats/gexf12 gonum.org/v1/gonum/graph/multi Standard library imports encoding/xml errors flag fmt io log net/mail os regexp sort strings time