code: def read_hierarchy(self, fid):
          
  
          lin = self.read_line(fid)
                      
          while lin != 'end':
              parts = lin.split()
              if lin != 'begin':
                  ind = self.get_index_by_name(parts[0])
                  for i in range(1, len(parts)):
                      self.vertices[ind].children.append(self.get_index_by_name(parts[i]))
              lin = self.read_line(fid)
          lin = self.read_line(fid)
          return lin
docs: Read hierarchy information from acclaim skeleton file stream.