cropping an image in a circular way ang paste on another image, using python

I am trying to crop an image in python in circular shape. And I also want to paste that image on the top of another image, and then then then save the image in a desired format.

This is the image that I want to crop in circular way

This is how the image should be looked like after cropping

This is the image on which I want to paste the circular shaped image

This is my expected output

Here is the code, as far I tried

from PIL import Image, ImageDraw, ImageFilter

im1 = Image.open('rocket.jpg')
im2 = Image.open('lena.jpg')

width, height = im1.size
print(height, width)

mask_im = Image.new("L", im2.size, 0)
draw = ImageDraw.Draw(mask_im)
draw.ellipse((150, 40, 250, 100), fill=255)
mask_im.save('mask_circle.jpg', quality=95)

back_im = im1.copy()
back_im.paste(im2, (0, 0), mask_im)
back_im.save('rocket_pillow_paste_mask_circle.jpg', quality=95)

mask_im_blur = mask_im.filter(ImageFilter.GaussianBlur(10))
mask_im_blur.save('mask_circle_blur.jpg', quality=95)

back_im = im1.copy()
back_im.paste(im2, (0, 0), mask_im_blur)
back_im.save('rocket_pillow_paste_mask_circle_blur.jpg', quality=95)

Answer

from PIL import Image, ImageDraw, ImageFilter


im1 = Image.open('rocket.jpg')
im2 = Image.open('lena.jpg')

#height, width, channels = im1.shape
width, height = im1.size
print(height, width)


# ![rocket_pillow_paste_out](data/dst/rocket_pillow_paste_out.jpg)

mask_im = Image.new("L", im2.size, 0)
draw = ImageDraw.Draw(mask_im)
draw.ellipse((140, 50, 260, 170), fill=255)
mask_im.save('mask_circle.jpg', quality=95)

back_im = im1.copy()
back_im.paste(im2, (0, 0), mask_im)
back_im.save('rocket_pillow_paste_mask_circle.jpg', quality=95)

# ![rocket_pillow_paste_mask_circle](data/dst/rocket_pillow_paste_mask_circle.jpg)

mask_im_blur = mask_im.filter(ImageFilter.GaussianBlur(10))
mask_im_blur.save('mask_circle_blur.jpg', quality=95)

back_im = im1.copy()
back_im.paste(im2, (0, 0), mask_im_blur)
back_im.save('rocket_pillow_paste_mask_circle_blur.jpg', quality=95)

# ![rocket_pillow_paste_mask_circle_blur](data/dst/rocket_pillow_paste_mask_circle_blur.jpg)