Tkinter error TclError: invalid command name ".71847552" : I am making an excel comparing program and exporting it to a CSV file. Here is my code:

    import openpyxl, csv
    from tkinter import *
    from tkinter.filedialog import askopenfilename
    from openpyxl.utils import column_index_from_string

    output = open('differences.csv', 'w', newline='')
    output_writer = csv.writer(output)

    wb1, wb2 = '', ''
    sheet1, sheet2 = '', ''
    column_1, column_2 = '', ''

    root = Tk()
    root.configure(background='light green')
    root.geometry("500x500")
    root.wm_title("BananaCell")

    e1 = Text(root, width=15, height=1)
    e1.pack()
    e1.place(x=70, y=150)

    e2 = Text(root, width=15, height=1)
    e2.pack()
    e2.place(x=300, y=150)

    column1_entry = Text(root, width=5, height=1)
    column1_entry.pack()
    column1_entry.place(x=135, y=250)

    column2_entry = Text(root, width=5, height=1)
    column2_entry.pack()
    column2_entry.place(x=385, y=250)


    def destroy():
        root.destroy()

    def ask_for_filename_1():
        global wb1
        wb1 = askopenfilename(title="Select Workbook 1")
        print(str(wb1))
        return wb1


    def ask_for_filename_2():
        global wb2
        wb2 = askopenfilename(title="Select Workbook 1")
        print(str(wb2))
        return wb2


    def ask_for_sheet1():
        global sheet1
        sheet1 = e1.get("1.0", "end-1c")
        print(sheet1)
        return sheet1


    def ask_for_sheet2():
        global sheet2
        sheet2 = e2.get("1.0", "end-1c")
        print(sheet2)
        return sheet2


    def get_col_1():
        global column_1
        column_1 = column1_entry.get("1.0", "end-1c")
        print(column_1)
        return column_1


    def get_col_2():
        global column_2
        column_2 = column2_entry.get("1.0", "end-1c")
        print(column_2)
        return column_2


    filename_button1 = Button(root, text="Workbook 1", width=12, height=2, command=ask_for_filename_1)
    filename_button1.pack()
    filename_button1.place(x=100, y=100)

    filename_button2 = Button(root, text="Workbook 2", width=12, height=2, command=ask_for_filename_2)
    filename_button2.pack()
    filename_button2.place(x=300, y=100)

    col_button1 = Button(root, text="Enter", width=5, height=1, command=get_col_1)
    col_button1.pack()
    col_button1.place(x=185, y=248)

    col_button2 = Button(root, text="Enter", width=5, height=1, command=get_col_2)
    col_button2.pack()
    col_button2.place(x=435, y=248)

    sheet_button1 = Button(root, text="Enter", width=6, height=0, command=ask_for_sheet1)
    sheet_button1.pack()
    sheet_button1.place(x=15, y=147)

    sheet_button2 = Button(root, text="Enter", width=6, height=0, command=ask_for_sheet2)
    sheet_button2.pack()
    sheet_button2.place(x=430, y=147)

    label1 = Label(root, text="Sheet 1 column letter: ", bg="light green")
    label1.pack()
    label1.place(x=10, y=250)

    label2 = Label(root, text="Sheet 2 column letter: ", bg = "light green")
    label2.pack()
    label2.place(x=260, y=250)


    def write_csv(col1, col2, worksheet1, worksheet2):
        for (col, col_1) in zip(worksheet1.iter_cols(min_col = column_index_from_string(col1), max_col=column_index_from_string(col1)), worksheet2.iter_cols(min_col = column_index_from_string(col2), max_col=column_index_from_string(col2))):
            for (cell, cell_1) in zip(col, col_1):
               if cell.value != cell_1.value and cell.row == cell_1.row:
                   output_writer.writerow(['Sheet 1 value: ' + ' ' + str(cell.value) + '  ' + 'is not equal to ' + '  ' + 'Sheet 2 value:  ' + ' ' + str(cell_1.value) + ' ' + 'on row ' + ' ' + str(cell.row)])


    dButton = Button(root, text="Exit", width=8, height=1, command=destroy)
    dButton.pack()
    dButton.place(x=100, y=60)


    mainloop()

    workbook1 = openpyxl.load_workbook(str(wb1))
    workbook2 = openpyxl.load_workbook(str(wb2))

    global sheet1
    sheet1 = e1.get("1.0", "end-1c")

    global sheet2
    sheet2 = e2.get("1.0", "end-1c")


    worksheet1 = workbook1.get_sheet_by_name(str(sheet1))
    worksheet2 = workbook2.get_sheet_by_name(str(sheet2))

    col1 = column1_entry.get("1.0", "end-1c")
    col2 = column2_entry.get("1.0", "end-1c")

    write_csv(col1, col2, worksheet1, worksheet2)


However, when I run the follwing code, I enter the criteria required and end up with the following error: `_tkinter.TclError: invalid command name ".71847552"`.
Does anyone know how to fix this issue? Any help would be massively appreciated

