code: def parse_struct(path_dir):
          
          with open(os.path.join(path_dir, "boltztrap.struct"), 'r') as f:
              tokens = f.readlines()
              return Lattice([[Length(float(tokens[i].split()[j]), "bohr").
                             to("ang") for j in range(3)] for i in
                              range(1, 4)]).volume
docs: Parses boltztrap.struct file (only the volume)
          Args:
              path_dir: (str) dir containing the boltztrap.struct file
  
          Returns:
              (float) volume