text: class AttentionMatrix:
      def __init__(self, src_tokens, tgt_tokens, matrix):
          self._src_tokens = src_tokens
          self._tgt_tokens = tgt_tokens
          self._matrix = matrix
  
      def get_src_tokens(self):
          return self._src_tokens
      src_tokens = property(get_src_tokens)
  
      def get_tgt_tokens(self):
          return self._tgt_tokens
      tgt_tokens = property(get_tgt_tokens)
  
      def get_matrix(self):
          return self._matrix
      matrix = property(get_matrix)
  
  