Cannot show a png image in a Tkinter canvas object

Question

I'm trying to show a .png image in a canvas inside the main window, but what I get in the canvas is just a blue background. Please can you help me show the image instead of the blue background?

import os
import tkinter as tk


class MyApplication(tk.Tk):
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.title('Program')
        self.geometry('500x300')

        folder = os.path.dirname(__file__)
        self.canvas = tk.Canvas(self, bg='blue', height=300, width=300)
        self.canvas.pack()
        my_image = tk.PhotoImage(file=folder+'/1102157.png')
        self.canvas.create_image(0, 0, anchor = tk.NW, image=my_image)


if __name__=='__main__':
    app = MyApplication()
    app.mainloop()

I tried to put

folder = os.path.dirname(__file__)

before the class MyApplication but it still does not work.