Change image on canvas to a new image the user selects using tkinter

Question

The canvas has a placeholder image in place. when I select a new image from the pop up window, the canvas just becomes blanks. Any help would be much appreciated. Here is the code so far...

import tkinter.filedialog
from tkinter import *
import tkinter.font as font
import tkfilebrowser as tkf
from PIL import ImageTk, Image



def select_image():
                                 ])
    selected_image = Image.open(file)
    image_resized = selected_image.resize((1100, 700), Image.ANTIALIAS)
    formatted_image = ImageTk.PhotoImage(image_resized)
    canvas.itemconfigure(image_on_canvas, image=formatted_image)


window = Tk()
window.title('Watermark')
window.minsize(1200, 800)
window.maxsize(1200, 800)

button_font = font.Font(family='Blackoak Std')


placeholder_image = Image.open('Bladerunner.jpg')
resized_placeholder_image = placeholder_image.resize((1100, 700), Image.ANTIALIAS)
placeholder = ImageTk.PhotoImage(resized_placeholder_image)


canvas = Canvas(width=1100, height=700)
canvas.place(x=50, y=5)
image_on_canvas = canvas.create_image(550, 400, image=placeholder)

select_image_button = Button(text='Upload Image', font=button_font, command=select_image)
select_image_button.place(x=350, y=730)

watermark_button = Button(text='Watermark', font=button_font)
watermark_button.place(x=550, y=730)

save_button = Button(text='Save', font=button_font, width=10)
save_button.place(x=730, y=730)

window.mainloop()