def get_line_numbers():
    output = ''
    if show_line_number.get():
        (row, col) = my_text.index('end').split('.')
        for i in range(1, int(row)):
            output += (str(i) + '\n')
    return output
def get_line_numbers():
    output = 
    if show_line_number.get():
        (row, col) = my_text.index('end').split('.')
        for i in range(1, int(row)):
            output += (str(i) + '\n')
    return output