老师不知道什么原因，然后代码打完没有出现弹窗

老师问几个小问题：

1。

 div>p:first-child

p:last-child

这两个选择器是关系选择器对么

2.

input:checked

div>p:nth-child(even)

div>p:nth-child(odd)

这个是伪类选择器对吗

老师我看课件文档中，标准类视图必须继承flask.views.View

我在写代码时，写的是：

import flask

class ListView(flask.views.View):

会报错：AttributeError：views

只有写成

import flask

from flask.views import View

class ListView(View):

才不会报错，这是什么原因，一直没明白这其中的原理。

系统错别字。安装移动开发    安卓移动开发。   因为字错了我才没选导致扣分了该怎么办呢。

vite.config.js在哪个文件夹啊

为什么我的无法运行？

这个“\n"为什么不是以字符串的形式加到后面，而是实现换行的功能呢？

请问这个数据库设置商品状态值1,2,3 ，这个123 从前端哪里 对应这个状态，不从数据库中的备注中看

红色圈出部分是不是打错了？

sum+=na+="sxt";sum=sum+na=na+"sxt"

num-=n;mun=mun-n

1. 为什么这里Drawing类里的account能调用Account里的name

2. expenseTotal不需要在def__init__()括号里定义吗

;

;
;
;
;

{
    (,){
        ;
        ;
        {
            .();
            .(,,);
            ;
            .();
            .();
            ..();
        } () {
            .();
        }{
            (){
                {
                    .();
                } () {
                    .();
                }
            }
        }
        (){
            {
                .();
            } () {
                .();
            }
        }
    }
    ([] ) {
        ();
        .(,);
    }
}

报错，

"C:\Program Files\Java\jdk1.8.0_201\bin\java.exe" "-javaagent:D:\program files\JetBrains\IntelliJ IDEA 2019.1\lib\idea_rt.jar=49766:D:\program files\JetBrains\IntelliJ IDEA 2019.1\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_201\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_201\jre\lib\rt.jar;D:\workspace\jdbcDemo\out\production\jdbcDemo;D:\workspace\jdbcDemo\lib\mysql-connector-java-5.1.47.jar" com.bjsxt.JdbcTest

Sat Nov 02 21:15:19 CST 2019 WARN: Establishing SSL connection without server's identity verification is not recommended. According to MySQL 5.5.45+, 5.6.26+ and 5.7.6+ requirements SSL connection must be established by default if explicit option isn't set. For compliance with existing applications not using SSL the verifyServerCertificate property is set to 'false'. You need either to explicitly disable SSL by setting useSSL=false, or set useSSL=true and provide truststore for server certificate verification.

java.sql.SQLException: Access denied for user 'root'@'localhost' (using password: YES)

at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:965)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3978)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3914)

at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:871)

at com.mysql.jdbc.MysqlIO.proceedHandshakeWithPluggableAuthentication(MysqlIO.java:1714)

at com.mysql.jdbc.MysqlIO.doHandshake(MysqlIO.java:1224)

at com.mysql.jdbc.ConnectionImpl.coreConnect(ConnectionImpl.java:2199)

at com.mysql.jdbc.ConnectionImpl.connectOneTryOnly(ConnectionImpl.java:2230)

at com.mysql.jdbc.ConnectionImpl.createNewIO(ConnectionImpl.java:2025)

at com.mysql.jdbc.ConnectionImpl.<init>(ConnectionImpl.java:778)

at com.mysql.jdbc.JDBC4Connection.<init>(JDBC4Connection.java:47)

at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)

at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)

at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)

at java.lang.reflect.Constructor.newInstance(Constructor.java:423)

at com.mysql.jdbc.Util.handleNewInstance(Util.java:425)

at com.mysql.jdbc.ConnectionImpl.getInstance(ConnectionImpl.java:386)

at com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:330)

at java.sql.DriverManager.getConnection(DriverManager.java:664)

at java.sql.DriverManager.getConnection(DriverManager.java:247)

at com.bjsxt.JdbcTest.insertDepartments(JdbcTest.java:17)

at com.bjsxt.JdbcTest.main(JdbcTest.java:44)

Process finished with exit code 0

老师怎么解决？？？

index_url ='https://www.kuaidaili.com/usercenter/overview'
index_req = Request(index_url,headers =headers)
index_resp = opener.open(index_req)
print(index_resp.read().decode())

请问这里是什么意思，在登录账号后，还发送请求是为啥

老师我把找到问题在哪了///        给老师添麻烦了

headers={"UserAgent":UserAgent().random}里的UserAgent写错了，应该这么写User-Agent。

String s = new String("北京尚学堂");

老师，这个代码里是有两个对象么？一个是new,一个是传入的？