def e_timeToString(dateString):
    """
    input: string
    output: string
    description: format dateString to yyyymmddHHMM
    example: Wed Aug 29 07:23:03 CST 2018 ->> 201808290723
    """
    # define month list for get digital
    month = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep",
             "Oct", "Nov", "Dec"]
    year_string = dateString[-4:]
    month_string = str(month.index(dateString[4:7]) + 1)
    if len(month_string) == 1:
        month_string = "0" + month_string
    day_string = dateString[8:10]

    # time format HHMM
    time_string = dateString[11:16].replace(":", "")

    return year_string + month_string + day_string + time_string