code: def pairwise_iter(src):
      """Convenience function for calling :func:`windowed_iter` on *src*,
      with *size* set to 2.
      >>> list(pairwise_iter(range(5)))
      [(0, 1), (1, 2), (2, 3), (3, 4)]
      >>> list(pairwise_iter([]))
      []
  
      The number of pairs is always one less than the number of elements
      in the iterable passed in, or zero, when *src* is empty.
      """
      return windowed_iter(src, 2)
  
imports: import os
  import math
  import time
  import codecs
  import random
  import socket
  import hashlib
  import itertools
  from collections import Mapping, Sequence, Set, ItemsView
label_desc: Use image node_id 9 for calling a global function with example usage: pairwise_iter(src) and returns: windowed_iter