How to apply cloudinary transformations outside of templates

[justuswilhelm]

I am storing a profile picture for each user in our database.

class User(AbstractBaseUser, PermissionsMixin):
    profile_picture = models.ImageField(
        upload_to="profile_picture/",
        blank=True,
        null=True,
    )

Now, I would like to return a cropped or otherwise transformed version of the profile_picture to a client requesting it via a REST API. What method can I use to get a CloudinaryImage instance of the image?