def _setUnits(value):
	"""
	Convert a value in bytes so a human-readable format with units.
	"""
	
	if value > 1024.0**3:
		value = value / 1024.0**3
		unit = 'GB'
	elif value > 1024.0**2:
		value = value / 1024.0**2
		unit = 'MB'
	elif value > 1024.0**1:
		value = value / 1024.0*1
		unit = 'kB'
	else:
		unit = ' B'
	return value, unit