PyQt5 lable 显示 DoubleSpinBox 值时小数精度问题

请问，PyQt5 lable 显示 DoubleSpinBox 值时小数精度问题，到0.009以后就异常了，求指导


 -*- coding: utf-8 -*-

# Form implementation generated from reading ui file 'DoubleSpinBox.ui'
#
# Created by: PyQt5 UI code generator 5.15.4
#
# WARNING: Any manual changes made to this file will be lost when pyuic5 is
# run again.  Do not edit this file unless you know what you are doing.


from PyQt5 import QtCore, QtGui, QtWidgets


class Ui_MainWindow(object):
    def setupUi(self, MainWindow):
        MainWindow.setObjectName("MainWindow")
        MainWindow.resize(532, 170)
        self.centralwidget = QtWidgets.QWidget(MainWindow)
        self.centralwidget.setObjectName("centralwidget")
        self.doubleSpinBox = QtWidgets.QDoubleSpinBox(self.centralwidget)
        self.doubleSpinBox.setGeometry(QtCore.QRect(100, 40, 351, 31))
        self.doubleSpinBox.setDecimals(3)
        self.doubleSpinBox.setMinimum(0)
        self.doubleSpinBox.setMaximum(99.999)
        self.doubleSpinBox.setSingleStep(0.001)
        self.doubleSpinBox.setStepType(QtWidgets.QAbstractSpinBox.DefaultStepType)
        self.doubleSpinBox.setObjectName("doubleSpinBox")
        self.label = QtWidgets.QLabel(self.centralwidget)
        self.label.setGeometry(QtCore.QRect(100, 90, 131, 16))
        self.label.setObjectName("label")
        self.label_2 = QtWidgets.QLabel(self.centralwidget)
        self.label_2.setGeometry(QtCore.QRect(230, 90, 211, 16))
        self.label_2.setText("")
        self.label_2.setObjectName("label_2")
        self.doubleSpinBox.valueChanged.connect(self.getvalue)
        MainWindow.setCentralWidget(self.centralwidget)

        self.retranslateUi(MainWindow)
        QtCore.QMetaObject.connectSlotsByName(MainWindow)

    def retranslateUi(self, MainWindow):
        _translate = QtCore.QCoreApplication.translate
        MainWindow.setWindowTitle(_translate("MainWindow", "MainWindow"))
        self.label.setText(_translate("MainWindow", "当前控件中显示的数值："))

    def getvalue(self):
        self.label_2.setText(str(self.doubleSpinBox.value()))


import sys #程序入口，从此处启动PyQt设计窗体
if __name__ == "__main__":
    app = QtWidgets.QApplication(sys.argv)
    MainWindow = QtWidgets.QMainWindow()    #创建窗体对象
    ui = Ui_MainWindow()                   # 创建 PYQT 设计的窗体对象
    ui.setupUi(MainWindow)                 # 调用Pyqt窗口方法，对窗体对象初始化设置。
    MainWindow.show()                      # 显示窗体
    sys.exit(app.exec_())                  # 退出结束进程

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