code: def reciprocal_lattice(self) -> "Lattice":
          
          v = np.linalg.inv(self._matrix).T
          return Lattice(v * 2 * np.pi)
docs: Return the reciprocal lattice. Note that this is the standard
          reciprocal lattice used for solid state physics with a factor of 2 *
          pi. If you are looking for the crystallographic reciprocal lattice,
          use the reciprocal_lattice_crystallographic property.
          The property is lazily generated for efficiency.