SELECT tags, geom
FROM postpass_polygon
WHERE
(
  -- Bounding box: City of Livorno.
  ST_Intersects(geom, ST_MakeEnvelope(9.888339, 43.419635, 10.419938, 43.595488, 4326))
  -- Type of entries: Administrative subdivisions.
  AND tags->>'admin_level'='10'
  -- Entity: Consiglio di Zona 6 (https://www.wikidata.org/wiki/Q138390892).
  AND tags->>'wikidata'='Q138390892'
)