关于PyQt5的问题?

import sys

from PyQt5.QtWidgets import (QWidget, QApplication, QGridLayout,

                             QLineEdit, QPushButton)

class CalcUi(QWidget):

    def __init__(self):

        QWidget.__init__(self)

        self.generalDict = {}

        self.setWindowTitle("Calc")

        self.initUi()

    def initUi(self):

        uiDict = {'Row1': ('7', '8', '9', '/'),

                  'Row2': ('4', '5', '6', '*'),

                  'Row3': ('1', '2', '3', '+'),

                  'Row4': ('-', '0', '.', '='),

                  'Row5': ('c'               ),

                  }

        qGridLayout = QGridLayout(self)

        inputLine = QLineEdit()

        qGridLayout.addWidget(inputLine, 0, 0, 1, 4)

        for line in uiDict:

            for labelIndex in range(len(uiDict[line])):

                btn = QPushButton(uiDict[line][labelIndex])

                btn.setToolTip(btn.text())

                self.generalDict[btn] = btn.text()

                if len(uiDict[line]) == 1:

                    qGridLayout.addWidget(btn, 5, 0, 1, 4)

                else:

                    qGridLayout.addWidget(btn)



        for func, label in self.generalDict.items():

            # 这个位置点击事件后,打印出来的w类型为bool类型

            func.clicked.connect(lambda w=func:print(type(w)))  



if __name__ == '__main__':

    app = QApplication(sys.argv)

    win = CalcUi()

    win.show()

    sys.exit(app.exec_())

if __name__ == '__main__':

    add = lambda x=5: print(type(x))

    add()  # 这个位置打印出来的x的类型为int型,符合原x类型