code: def pairwise(src):
      """Convenience function for calling :func:`windowed` on *src*, with
      *size* set to 2.
      >>> pairwise(range(5))
      [(0, 1), (1, 2), (2, 3), (3, 4)]
      >>> pairwise([])
      []
  
      The number of pairs is always one less than the number of elements
      in the iterable passed in, except on empty inputs, which returns
      an empty list.
      """
      return windowed(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 8 for calling a global function with example usage: pairwise(src) and returns: windowed