Как Привязать данные, введённые в Entry Widget к списку?

from tkinter import *
import tkinter.ttk as ttk
 
team1Members = []
team2Members = []
team3Members = []
team4Members = []
 
 
class CollegeApp(Tk):
    def __init__(self):
        Tk.__init__(self)
        container = ttk.Frame(self)
        container.pack(side="top", fill="both", expand=True)
        self.frames = {}
        for F in (StartPage, selectionPage, TeamsPage):
            frame = F(container, self)
            self.frames[F] = frame
            frame.grid(row=0, column=0, sticky="nsew")
        self.show_frame(StartPage)
 
    def show_frame(self, cont):
        frame = self.frames[cont]
        frame.tkraise()
 
 
class StartPage(ttk.Frame):
    def __init__(self, parent, controller):
        self.controller = controller
        ttk.Frame.__init__(self, parent)
        self.startMenu()
 
    def startMenu(self):
        heading = Label(self, text="College Tournament Points\n Count Software",
                        font=('Arial', 25))
        heading.grid(row=0, column=0, columnspan=2, padx=240, pady=40)
 
        start_Btn = Button(self, text="Start", font="Arial 16", width=8,
                           command=lambda: self.controller.show_frame(selectionPage))
        start_Btn.grid(row=1, column=0, padx=30, pady=5)
 
        exit_Btn = Button(self, text="EXIT", font="Arial 16", width=8,
                          command=self.controller.destroy)
        exit_Btn.grid(row=1, column=1, padx=30, pady=5)
 
    def starting_Program(self):
        pass
 
 
class selectionPage(ttk.Frame):
    def __init__(self, parent, controller):
        self.controller = controller
        ttk.Frame.__init__(self, parent)
        self.teamSelect()
 
    def teamSelect(self):
        heading = Label(self, text="Become a member of a Team",
                        font=('Arial', 25))
        heading.grid(row=0, column=0, columnspan=2, padx=200, pady=40)
 
        teams = Button(self, text="Teams", font="Arial 24", width=15,
                       command=lambda: self.controller.show_frame(TeamsPage))
        teams.grid(row=1, column=0, padx=270, pady=5)
 
class TeamsPage(ttk.Frame):
 
    def __init__(self, parent, controller):
        self.controller = controller
        ttk.Frame.__init__(self, parent)
        self.userEntry()
 
    def userEntry(self):
        headingTest = Label(self, text="Enter your Username:", font="Arial 20")
        headingTest.grid(row=0, column=0, pady=0)
 
        usernameEnter = Entry(self, width=40)
        usernameEnter.grid(row=0, column=1, padx=2, pady=10)
 
        UserName = StringVar(self)
        UserName.set("Team1")
 
        AdditionalText = Label(self, text="Please select a team:", font="Arial 18") 
        AdditionalText.grid(row=1, column=0, sticky=W, pady=15)
 
        teamSelection = OptionMenu(self, UserName, "Team1", "Team2", "Team3", "Team 4") # How to link those variations to team list? For example: Team 1 = team1Members?
        teamSelection.grid(row=1, column=1, sticky=W)
 
        confirmBtn = Button(self, text="Submit", font="Arial 16",
                            command=()) # Command to Save username in teamXMembers list. Depends on the user selection 
        confirmBtn.config(height=4, width=12)
        confirmBtn.grid(row=2, column=2, sticky=E, padx=65, pady=300)
 
        
 
 
if __name__ == '__main__':
    app = CollegeApp()
    app.geometry("800x500")
    app.title('Points Counter')
    app.mainloop()