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截止目前，同学们一共提了 132885个问题

老师有个问题，父类调用那个地方为什么写成:

Frame.__init__(master)

会报错：AttributeError: 'Application' object has no attribute 'tk'

之前讲的不是说调用父类有两种方法吗？

Python 全系列/第二阶段：Python 深入与提高/GUI编程（隐藏） 19441楼

怎么用着变成这样了怎么恢复

Python 全系列/第二十一阶段：数据分析软件/数据可视化Tableau 19442楼

为啥我的3D图是空白

人工智能/第六阶段：机器学习-线性分类/逻辑回归 19443楼

老师为啥我这里有错呢，为啥调用不了copy函数呢

Python 全系列/第一阶段：Python入门/函数和内存分析 19444楼

老师老师，我不太理解，获取这个自增主键值，目前看仅仅是知道新数据的主键而已，但在实际开发中获取主键值还有什么更重要的意义吗？或者说我知道主键值之后可以拿来干什么？

JAVA 全系列/第六阶段：项目管理与SSM框架/Mybatis 19445楼

老师我不太懂为什么这里的抛出异常不需要那么繁琐的步骤或者为何不添加括号写里面呢?

JAVA 全系列/第二阶段：JAVA 基础深化和提高/异常机制 19446楼

老师，这个错误是啥原因造成的？

人工智能/第二阶段：人工智能基础-Python基础/Python基础语法-旧 19447楼

进d盘的时候显示不是内部命令或外部命令，也不是可运行的程序是怎么回事

JAVA 全系列/第一阶段：JAVA 快速入门/JAVA入门和背景知识 19448楼

老师，我想问一下，这个主机和客户端难道不是指的同一台电脑吗，为什么它们的IP不一样：

JAVA 全系列/第二阶段：JAVA 基础深化和提高/网络编程（旧） 19449楼

老师，我如果把education_num，分箱后的age、fnlwgt这些貌似是有序的做成labelencode编码，其他离散变量做成one-hot编码，这样可行吗

Python 全系列/第二十一阶段：Python_数据分析项目（旧）/工资分类预测 19450楼

<!DOCTYPE 根元素名称 SYSTEM  "dtd路径">
这里这个dtd路径是。。。
dtd文件和xml文件在同一个文件夹下，可以直接写文件名
我印象中，之前学javaSE的时候，直接写名称，应该指的是当前项目下啊

JAVA 全系列/第五阶段：JavaWeb开发/XML技术（旧） 19451楼

老师，这个在构造器里重写方法那为什么还有在Student类里面重写equals和hashcode方法，能不重写吗

JAVA 全系列/第二阶段：JAVA 基础深化和提高/容器（旧） 19452楼

老师，我在执行make命令出现这个错误，如果重新安装的话怎样清除掉以下载的内容

JAVA 全系列/第十一阶段：分布式RPC调用和分布式文件存储/FastDFS 19453楼

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <link rel="stylesheet" href="./iconfont.css">
    <style>
        *{
            margin: 0;
            padding: 0;
        }
        body{
            background-color: #f1f1f1;
        }
        .slide{
            width: 234px;
            height: 420px;
            background-color: rgba(105,101,101,0.6);
            padding: 20px 0;
            margin: 100px;
            position: relative;
        }
        .slide ul{
            list-style: none;
        }
        .slide ul li{
            width: 100%;
            height: 42px;
            line-height: 42px;
            text-align: left;
            padding-left: 30px;
            box-sizing: border-box;
        }
        .slide ul li:hover{
            background-color: #ff6700;
           
        }
        .slide ul li a{
            display: inline-block;
            text-decoration: none;          
            color: #fff;
           
        }
       
        .slide .iconfont{
            display: inline-block;
            font-size: 24px;
            color: #fff;
            position: absolute;
            right: 10px;
        }
        .slide-list{
            width: 992px;
            height: 460px;
            background-color: #fff;
            position: absolute;
            top: 0;
            left: 234px;
            border: 1px solid #e0e0e0;
            border-left:none ;
            box-sizing: border-box;
            box-shadow: 0 4px 16px rgba(0,0,0,0.18);
            display: none;
            overflow: hidden;
            clear: both;
        }
        /* 鼠标滑动到li标签上，对应的div出现 */
        .slide ul li:hover>.slide-list{
            display: block;
        }
        .slide-list .text{
            display: block;
            width: 208px;
            height: 70px;
            line-height: 70px;
            /* background-color: red;     */
            float: left;
            margin-left: 30px;
            margin-top: 7px;
            font-size:normal;
        }
        .slide-list .text:hover>i{
            color: #ff6700;

        }
        .slide-list .text img{
            display: inline-block;
            /* 垂直对齐方式 */
            vertical-align: middle;
           
           
        }
        .slide-list .text i{
            font-size:normal;
            display: inline-block;
            color:black;
            font-size: 16px;  
        }
    </style>
</head>
<body>

    <div class="slide">
        <ul>
            <li>
                <a href="#">手机</a>
                <span class="iconfont icon-jiantou"></span>
                <div class="slide-list">
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" alt="">
                        <i>Redmi K50</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Redmi K50 Pro.webp" >
                        <i>Redmi K50 Pro</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 12X.webp" alt="">
                        <i>Xiaomi 12X</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi Civi.webp" alt="">
                        <i>Xiaomi Civi</i>
                    </a>
                    <a  class="text" href="#">
                        <img src="./Xiaomi 10S.webp" alt="">
                        <i>Xiaomi 10S</i>
                    </a>
                   
                </div>
            </li>
            <li>
                <a href="#">电视</a>
                <span class="iconfont icon-jiantou"></span>
                <div class="slide-list">小米2</div>
            </li>
        </ul>
    </div>
   
</body>
</html>

为什么这个字体我设置的normal但是还是斜体

WEB前端全系列/第一阶段：HTML5+CSS3模块/CSS应用技巧 19454楼

老师我还是访问不到资源为什么哇

JAVA 全系列/第五阶段：JavaWeb开发/Servlet技术详解 19455楼

同学您好