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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def upload_to_picture(instance, filename):
 """ Uploads a picture for a user to the ``ACCOUNTS_PICTURE_PATH`` and saving it under unique hash for the image. This is for privacy reasons so others can't just browse through the picture directory. """

    extension = filename.split('.')[-1].lower()
    salt, hash = generate_sha1(instance.id)
    return '%(path)s/%(hash)s.%(extension)s' % {
                'path': getattr(defaults, 
                            'ACCOUNTS_PICTURE_PATH','%s/%s' % (
                                str(instance._meta.app_label), 
                                str(instance._meta.model_name))),
                'hash': hash[:10],
                'extension': extension}