def zoneToRegion(zone):
    """Get a region (e.g. us-west-2) from a zone (e.g. us-west-1c)."""
    from toil.lib.context import Context
    return Context.availability_zone_re.match(zone).group(1)
Get a region (e.g. us-west-2) from a zone (e.g. us-west-1c).