import bpy
import sys
import os.path

try:
    outfile = open('vertgroup_mapping.txt', 'w')
    activeO = bpy.context.selected_objects[0]
    outfile.write("# MH Mesh vertex mapping for "+activeO.data.name +"n")
    idx = 0
    for g in activeO.vertex_groups:
        outfile.write("vertgroup "+ str(idx) +" "+ g.name +"n")
        idx = idx +1
    outfile.write("n")
    idx = 0
    for v in activeO.data.vertices:
        line = str(idx) + "t"
        for g in v.groups:
            line = line + str(g.group) + " "
        outfile.write(line + "n")
        idx = idx +1
    outfile.close()