# Python code
import maya.cmds as mc
import maya.mel as mm
# cast mel variable to Python:
gPlayBackSlider = mm.eval("$g = $gPlayBackSlider")
# Is anything highlighted?
rangeHighlighted = mc.timeControl(gPlayBackSlider, query=True, rangeVisible=True)
# What is the highlight range?
highlightedRange = mc.timeControl(gPlayBackSlider, query=True, rangeArray=True)
print rangeHighlighted, highlightedRange
# 1 [9.0, 17.0]
or
import pymel.core as pm
tc = pm.language.melGlobals["gPlayBackSlider"]
first,last = pm.timeControl(tc, rangeArray=True, query=True)