code: def get_wulff_shape(self, material_id):
          
          from pymatgen.symmetry.analyzer import SpacegroupAnalyzer
          from pymatgen.analysis.wulff import WulffShape, hkl_tuple_to_str
  
          structure = self.get_structure_by_material_id(material_id)
          surfaces = self.get_surface_data(material_id)["surfaces"]
          lattice = (SpacegroupAnalyzer(structure)
                     .get_conventional_standard_structure().lattice)
          miller_energy_map = {}
          for surf in surfaces:
              miller = tuple(surf["miller_index"])
              # Prefer reconstructed surfaces, which have lower surface energies.
              if (miller not in miller_energy_map) or surf["is_reconstructed"]:
                  miller_energy_map[miller] = surf["surface_energy"]
          millers, energies = zip(*miller_energy_map.items())
          return WulffShape(lattice, millers, energies)
docs: Constructs a Wulff shape for a material.
  
          Args:
              material_id (str): Materials Project material_id, e.g. 'mp-123'.
          Returns:
              pymatgen.analysis.wulff.WulffShape