With no explanation, label text_A→text_B with either "not_related" or "related".
text_A: Jon Pertwee was in a series based on books.
text_B: Lissotesta conoidea is a species of minute sea snail , a marine gastropod mollusc , unassigned in the superfamily Seguenzioidea .. Seguenzioidea. Seguenzioidea. Lissotesta. Lissotesta. species. species. sea snail. sea snail. marine. marine ( ocean ). gastropod. gastropod. mollusc. mollusc. superfamily. superfamily ( biology )
not_related.