PyQt5 building library management system (3) -- Design of login page

Analysis

The logic of the login page is simple, as follows:
-User input student number and password (for security, plus input detection)
-Prompt if the password is wrong or the user name does not exist
-If correct, jump

Code:

import sys
from PyQt5.QtWidgets import *
from PyQt5.QtGui import QIcon, QFont
from PyQt5.QtCore import Qt
import qdarkstyle
import hashlib
from PyQt5.QtSql import *


class SignInWidget(QWidget):
    def __init__(self):
        super(SignInWidget, self).__init__()
        self.resize(900, 600)
        self.setWindowTitle("Welcome to the library management system")
        self.setUpUI()

    def setUpUI(self):
        self.Vlayout = QVBoxLayout(self)
        self.Hlayout1 = QHBoxLayout()
        self.Hlayout2 = QHBoxLayout()
        self.formlayout = QFormLayout()

        self.label1 = QLabel("Student ID: ")
        labelFont = QFont()
        labelFont.setPixelSize(18)
        lineEditFont = QFont()
        lineEditFont.setPixelSize(16)
        self.label1.setFont(labelFont)
        self.lineEdit1 = QLineEdit()
        self.lineEdit1.setFixedHeight(32)
        self.lineEdit1.setFixedWidth(180)
        self.lineEdit1.setFont(lineEditFont)
        self.lineEdit1.setMaxLength(10)

        self.formlayout.addRow(self.label1, self.lineEdit1)

        self.label2 = QLabel("Password: ")
        self.label2.setFont(labelFont)
        self.lineEdit2 = QLineEdit()
        self.lineEdit2.setFixedHeight(32)
        self.lineEdit2.setFixedWidth(180)
        self.lineEdit2.setMaxLength(16)
        passwordFont = QFont()
        passwordFont.setPixelSize(10)
        self.lineEdit2.setFont(passwordFont)

        self.lineEdit2.setEchoMode(QLineEdit.Password)
        self.formlayout.addRow(self.label2, self.lineEdit2)
        self.signIn = QPushButton("Land")
        self.signIn.setFixedWidth(80)
        self.signIn.setFixedHeight(30)
        self.signIn.setFont(labelFont)
        self.formlayout.addRow("", self.signIn)

        self.label = QLabel("Welcome to use USTC Library management system")
        fontlabel = QFont()
        fontlabel.setPixelSize(30)
        self.label.setFixedWidth(390)
        # self.label.setFixedHeight(80)
        self.label.setFont(fontlabel)
        self.Hlayout1.addWidget(self.label, Qt.AlignCenter)
        self.widget1 = QWidget()
        self.widget1.setLayout(self.Hlayout1)
        self.widget2 = QWidget()
        self.widget2.setFixedWidth(300)
        self.widget2.setFixedHeight(150)
        self.widget2.setLayout(self.formlayout)
        self.Hlayout2.addWidget(self.widget2, Qt.AlignCenter)
        self.widget = QWidget()
        self.widget.setLayout(self.Hlayout2)
        self.Vlayout.addWidget(self.widget1)
        self.Vlayout.addWidget(self.widget, Qt.AlignTop)

        self.signIn.clicked.connect(self.signInCheck)

    def signInCheck(self):
        studentId = self.lineEdit1.text()
        password = self.lineEdit2.text()
        if (studentId == "" or password == ""):
            print(QMessageBox.warning(self, "warning", "Student ID and password cannot be empty!", QMessageBox.Yes, QMessageBox.Yes))
            return
        # Open database connection
        db = QSqlDatabase.addDatabase("QSQLITE")
        db.setDatabaseName('./db/LibraryManagement.db')
        db.open()
        query = QSqlQuery()
        sql = "SELECT * FROM user WHERE user.StudentId='%s'" % (studentId)
        query.exec_(sql)
        db.close()

        hl = hashlib.md5()
        hl.update(password.encode(encoding='utf-8'))
        if (not query.next()):
            print(QMessageBox.information(self, "Tips", "The account does not exist!", QMessageBox.Yes, QMessageBox.Yes))
        else:
            if (studentId == query.value(0) and hl.hexdigest() == query.value(2)):
                print("Correct")
            else:
                print(QMessageBox.information(self, "Tips", "Password error!", QMessageBox.Yes, QMessageBox.Yes))
        return


if __name__ == "__main__":
    app = QApplication(sys.argv)
    app.setWindowIcon(QIcon("./images/MainWindow_1.png"))
    app.setStyleSheet(qdarkstyle.load_stylesheet_pyqt5())
    mainMindow = SignInWidget()
    mainMindow.show()
    sys.exit(app.exec_())

The effect is as follows