prefetched.py

def prefetched_related(instance, name, default=None):
    """
    Attempts to find and return prefetched data on a model.

    Usage:
        values, prefetched = prefetched_related(instance, 'name')

        values     : A list of prefetched values for the field.
        prefetched : True if the requested field was prefetched on the instance.
    """
    if hasattr(instance, '_prefetched_objects_cache'):

        # Use the prefetched values only if the requested field was prefetched.
        if name in instance._prefetched_objects_cache:
            return instance._prefetched_objects_cache[name], True

    return default, False