code: def new(self, length, blocknum):
          # type: (int, int) -> None
          '''
          A method to create a new UDF Long AD.
  
          Parameters:
           None.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('UDF Long AD already initialized')
  
          self.extent_length = length
          self.log_block_num = blocknum
          self.part_ref_num = 0  # FIXME: we should let the user set this
          self.impl_use = b'\x00' * 6
  
          self._initialized = Truf new(self, length, blocknum):
          # type: (int, int) -> None
          '''
          A method to create a new UDF Long AD.
  
          Parameters:
           None.
          Returns:
           Nothing.
          '''
          if self._initialized:
              raise pycdlibexception.PyCdlibInternalError('UDF Long AD already initialized')
  
          self.extent_length = length
          self.log_block_num = blocknum
          self.part_ref_num = 0  # FIXME: we should let the user set this
          self.impl_use = b'\x00' * 6
  
          self._initialized = True
docs: A method to create a new UDF Long AD.
  
          Parameters:
           None.
          Returns:
           Nothing.