upgrade ubuntu 16.04 to 18.04

Change-Id: I7ddb395b372d514647de418442fed2f1258f1986

python3/Dockerfile

@@ -4,7 +4,7 @@
 # PLEASE DO NOT EDIT IT DIRECTLY.
 #
 
-FROM ubuntu:16.04
+FROM ubuntu:18.04
 MAINTAINER xt
 
 COPY sources.list /etc/apt/sources.list
@@ -19,6 +19,8 @@ ENV PATH /usr/local/bin:$PATH
 # > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
 ENV LANG C.UTF-8
 
+ENV DEBIAN_FRONTEND noninteractive
+
 # extra dependencies (over what buildpack-deps already includes)
 RUN apt-get update && apt-get install -y --no-install-recommends \
 		build-essential \

python3/sources.list

-# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ xenial main restricted
-deb-src http://archive.ubuntu.com/ubuntu xenial main restricted #Added by software-properties
-deb http://mirrors.aliyun.com/ubuntu/ xenial main restricted
-deb-src http://mirrors.aliyun.com/ubuntu/ xenial main restricted multiverse universe #Added by software-properties
-deb http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted
-deb-src http://mirrors.aliyun.com/ubuntu/ xenial-updates main restricted multiverse universe #Added by software-properties
-deb http://mirrors.aliyun.com/ubuntu/ xenial universe
-deb http://mirrors.aliyun.com/ubuntu/ xenial-updates universe
-deb http://mirrors.aliyun.com/ubuntu/ xenial multiverse
-deb http://mirrors.aliyun.com/ubuntu/ xenial-updates multiverse
-deb http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse
-deb-src http://mirrors.aliyun.com/ubuntu/ xenial-backports main restricted universe multiverse #Added by software-properties
-deb http://archive.canonical.com/ubuntu xenial partner
-deb-src http://archive.canonical.com/ubuntu xenial partner
-deb http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted
-deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main restricted multiverse universe #Added by software-properties
-deb http://mirrors.aliyun.com/ubuntu/ xenial-security universe
-deb http://mirrors.aliyun.com/ubuntu/ xenial-security multiverse
+# deb cdrom:[Ubuntu 16.04 LTS _Xenial Xerus_ - Release amd64 (20160420.1)]/ bionic main restricted
+deb-src http://archive.ubuntu.com/ubuntu bionic main restricted #Added by software-properties
+deb http://mirrors.aliyun.com/ubuntu/ bionic main restricted
+deb-src http://mirrors.aliyun.com/ubuntu/ bionic main restricted multiverse universe #Added by software-properties
+deb http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted
+deb-src http://mirrors.aliyun.com/ubuntu/ bionic-updates main restricted multiverse universe #Added by software-properties
+deb http://mirrors.aliyun.com/ubuntu/ bionic universe
+deb http://mirrors.aliyun.com/ubuntu/ bionic-updates universe
+deb http://mirrors.aliyun.com/ubuntu/ bionic multiverse
+deb http://mirrors.aliyun.com/ubuntu/ bionic-updates multiverse
+deb http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse
+deb-src http://mirrors.aliyun.com/ubuntu/ bionic-backports main restricted universe multiverse #Added by software-properties
+deb http://archive.canonical.com/ubuntu bionic partner
+deb-src http://archive.canonical.com/ubuntu bionic partner
+deb http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted
+deb-src http://mirrors.aliyun.com/ubuntu/ bionic-security main restricted multiverse universe #Added by software-properties
+deb http://mirrors.aliyun.com/ubuntu/ bionic-security universe
+deb http://mirrors.aliyun.com/ubuntu/ bionic-security multiverse