Create thumbnails for images inside specific folders

Create thumbnails for images inside specific folders

I would like to create image thumbnails (250x250px) using Wand
(imagemagick) for python.
I want results to be similar to PHP's imagecopyresampled()** function with
no quality loss if possible.
My directory structure is the following:
> main folder (level 1) -> only one
>> company folder (level 2 - inside main folder) -> 286 company folders
>>> product folder (level 2 - inside each company folder)
>>> property folders (level 2 - inside each company folder) -> number
depending on number of properties that each company owns
>>>> imagename.jpg (level 3 - inside each property folder) -> number
depending on number of images.
>>>> imagename_thumb.jpg (level 3 - inside each property folder) -> old,
smaller thumbs, one for every original image in folder. These should
be deleted/replaced with new ones.
Now what i would like to achieve is to create thumbnail (as described
before) for every imagename.jpg image, replacing old imagename_thumb.jpg
images with new ones.
PLEASE NOTE: There are also some images inside product folder, but i dont
want to create thumbs for these, so is it possible to avoid this folder
when looping through files?
REASON: We recently decided to redesign the online app which uses bigger
thumbnail images. It is almost impossible to replace all the existing
smaller thumbnails by hand.



** Explanation of imagecopyresampled() function (crop, resample) for
better understanding what kind of thumbs i want to achieve:
imagecopyresampled() copies a rectangular portion of one image to another
image, smoothly interpolating pixel values so that, in particular,
reducing the size of an image still retains a great deal of clarity.
In other words, imagecopyresampled() will take a rectangular area from
src_image of width src_w and height src_h at position (src_x,src_y) and
place it in a rectangular area of dst_image of width dst_w and height
dst_h at position (dst_x,dst_y).
If the source and destination coordinates and width and heights differ,
appropriate stretching or shrinking of the image fragment will be
performed. The coordinates refer to the upper left corner. This function
can be used to copy regions within the same image (if dst_image is the
same as src_image) but if the regions overlap the results will be
unpredictable.