code: def get_pairs(word):
      r"""Return set of symbol pairs in a word. Word is represented as tuple of
      symbols (symbols being variable-length strings).
  
      Example:
          word = "texar"
          get_pairs(word)
          # {('t', 'e'), ('e', 'x'), ('x', 'a'), ('a', 'r')}
      """
      pairs = set()
      prev_char = word[0]
      for char in word[1:]:
          pairs.add((prev_char, char))
          prev_char = char
      return pairs
  
label_desc: Use image node_id 2 for calling a global function with example usage: get_pairs(word) and returns: pairs