{X : Type u_5} →
  [t : TopologicalSpace X] →
    {motive : TopologicalSpace.MetrizableSpace X → Sort u} →
      ([toPseudoMetrizableSpace : TopologicalSpace.PseudoMetrizableSpace X] → [toT0Space : T0Space X] → motive ⋯) →
        (t : TopologicalSpace.MetrizableSpace X) → motive t