如何将textbox的值传递到窗口PyQt5之外

from PyQt5.QtWidgets import QApplication, QMainWindow, QVBoxLayout, QWidget, QLineEdit, QPushButton
from PyQt5.QtCore import pyqtSignal, QObject

class Communicate(QObject):
    valueChanged = pyqtSignal(str)

class Window(QMainWindow):
    def __init__(self):
        super().__init__()
        self.initUI()

    def initUI(self):
        self.setWindowTitle("Textbox传值示例")
        self.setGeometry(300, 300, 300, 200)

        layout = QVBoxLayout()

        self.textbox = QLineEdit()
        layout.addWidget(self.textbox)

        button = QPushButton("传递值")
        button.clicked.connect(self.sendValue)
        layout.addWidget(button)

        widget = QWidget()
        widget.setLayout(layout)
        self.setCentralWidget(widget)

    def sendValue(self):
        value = self.textbox.text()
        self.communicate = Communicate()
        self.communicate.valueChanged.emit(value)

if __name__ == '__main__':
    import sys
    app = QApplication(sys.argv)
    window = Window()
    window.show()
    sys.exit(app.exec_())