import maya.cmds as cmds

vertSel = cmds.filterExpand( ex=True, sm=31)
vert = [0, 0, 0]
vertLen = len(vertSel)

print vertSel

print vertLen

print vertSel


for i in vertSel:
    store = cmds.pointPosition(i, w=True)
    print store
    vert[0] += store[0]
    vert[1] += store[1]
    vert[2] += store[2]

vert[0] = vert[0] / vertLen




print vert