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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 THUMBNAIL_OPTIONS(self):
 """ Set the size as a 2-tuple for thumbnailed images after uploading them. """

        from django.core.exceptions import ImproperlyConfigured

        size = self._setting('DJNG_THUMBNAIL_SIZE', (200, 200))
        if not (isinstance(size, (list, tuple)) and len(size) == 2 and isinstance(size[0], int) and isinstance(size[1], int)):
            raise ImproperlyConfigured("'DJNG_THUMBNAIL_SIZE' must be a 2-tuple of integers.")
        return {'crop': True, 'size': size}