如何使用django/python选择特定大小的随机图像?

我一直在使用这个小片段来选择随机图像。不过,我想将其更改为仅选择特定大小的图像。我在检查图像尺寸时遇到了麻烦。如果我使用get_image_dimensions(),我需要使用一个条件语句,它要求我允许异常。所以,我想我需要一些关于图像尺寸限制的指针。谢谢。

import os
import random
import posixpath
from django import template
from django.conf import settings

register = template.Library()

def is_image_file(filename):
    """Does `filename` appear to be an image file?"""
    img_types = [".jpg", ".jpeg", ".png", ".gif"]
    ext = os.path.splitext(filename)[1]
    return ext in img_types

@register.simple_tag
def random_image(path):
    """
    Select a random image file from the provided directory
    and return its href. `path` should be relative to MEDIA_ROOT.

    Usage:  <img src='{% random_image "images/whatever/" %}'>
    """
    fullpath = os.path.join(settings.MEDIA_ROOT, path)
    filenames = [f for f in os.listdir(fullpath) if is_image_file(f)]
    pick = random.choice(filenames)
    return posixpath.join(settings.MEDIA_URL, path, pick)