List all availability zones in the current region

def list_availability_zones(call=None):
    '''
    List all availability zones in the current region
    '''
    ret = {}

    params = {'Action': 'DescribeZones',
              'RegionId': get_location()}
    items = query(params)

    for zone in items['Zones']['Zone']:
        ret[zone['ZoneId']] = {}
        for item in zone:
            ret[zone['ZoneId']][item] = six.text_type(zone[item])

    return ret