Opening GUI Panels Based on File (PyQT5)

Question

To the point: I have several panels that I would like to access via a bar. In order to make things easier, I want to loop through the module and auto-populate my main window with the relevant panels. This is my first stab at GUI / PyQT5, so please let me know if there is a better way of doing this!

My issue is that when a triggered action occurs (clicking on the dropdown menu for FirstPanel for instance), the name that is pulled in showPanel is qt_set_sequence_auto_mnemonic, which seems to be the last name in inspect. I guess the openPanel connection isn't preserved somehow, or maybe it is impossible to loop through. I don't have a great understanding of how the triggered actions occur, but any advice would be welcome.

Here are my panels in the "panel" module:

from PyQt5.QtWidgets import *
from PyQt5.QtGui import *


class FirstPanel(QDialog):
    """
    First Panel.
    """
    def __init__(self, parent = None):
        super(FirstPanel, self).__init__(parent)
        layout = QVBoxLayout()
        self.name = "The first panel"
        self.label = QLabel(self.name)
        layout.addWidget(self.label)
        self.setLayout(layout)
        self.initUI()

    def initUI(self):
        """
        Initialize UI for Panel
        """
        self.setGeometry(300,300,300,220)
        self.setWindowTitle(self.name)



class SecondPanel(QDialog):
    """
    Second panel...
    """

Now, my main window will grab the relevant panels from this list and populate the drop bar:

import sys
from PyQt5.QtWidgets import *
from PyQt5.QtGui import QIcon
import inspect

import panels 

class Main_Window(QMainWindow):

    def __init__(self, parent = None):
        """
        Constructor for the Main_Window GUI. Inherits from QMainWindow.
        All other windows should be children. 
        """
        super(Main_Window, self).__init__(parent)
        self.initUI()

    def initUI(self):
        """
        Initializes menu and initial panels. 
        """
        self.initMenuBar()
        # Create window...
        self.setGeometry(300, 300, 300, 200)
        self.setWindowIcon(QIcon(''))
        self.setWindowTitle('Control Panels')
        self.show()

    def initMenuBar(self):
        """
        Initializes the main menu bar so that the user can safely
        open closed / unopened panels. As long as panel is defined
        in panels, it will be populated here!

        TO DO: Add more usability
        """
        self.statusBar()
        menubar = self.menuBar()
        panelMenu = menubar.addMenu('&Panels')
        # Add actions to the panel menu
        
        # Let's do an intuitive approach...
        # This will parse panels for available panels
        for name, obj in inspect.getmembers(panels):
            if str(obj).find('panels') != -1:
                if str(name).find('Panel') != -1:
                    openPanel = QAction(QIcon(), name, self)
                    openPanel.triggered.connect(lambda : self.showPanel(str(name)))
                    panelMenu.addAction(openPanel)        
        ### MORE MENU ITEMS ###
        return menubar
    
    """ Show Window Functions """
    def showPanel(self,panelString):
        """
        PyQT5 likes calling windows from external functions when connecting. 
        """
        print(panelString)
        win = getattr(panels, panelString)(self)
        win.show()

def main():
    app = QApplication(sys.argv)
    ex = Main_Window()
    sys.exit(app.exec_())

if __name__ == '__main__':
    main()

Finally, when I run the GUI and try to click on a panel in the drop bar this is the error:

qt_set_sequence_auto_mnemonic
Traceback (most recent call last):
  File "experiment_panel.py", line 59, in <lambda>
    openPanel.triggered.connect(lambda : self.showPanel(str(name)))
  File "experiment_panel.py", line 70, in showPanel
    win = getattr(panels, panelString)(self)
TypeError: qt_set_sequence_auto_mnemonic(bool): argument 1 has unexpected type 'Main_Window'