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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def getHighOrderSequenceChunk(it, switchover=1000, w=40, n=2048):
 """ Given an iteration index, returns a list of vectors to be appended to the input stream, as well as a string label identifying the sequence. This version generates a bunch of high order sequences. The first element always provides sufficient context to predict the rest of the elements. After switchover iterations, it will generate a different set of sequences. """

  if it%10==3:
    s = numpy.random.randint(5)
    if it <= switchover:
      if s==0:
        label="XABCDE"
      elif s==1:
        label="YCBEAF"
      elif s==2:
        label="GHIJKL"
      elif s==3:
        label="WABCMN"
      else:
        label="ZDBCAE"
    else:
      if s==0:
        label="XCBEAF"
      elif s==1:
        label="YABCDE"
      elif s==2:
        label="GABCMN"
      elif s==3:
        label="WHIJKL"
      else:
        label="ZDHICF"

    vecs = letterSequence(label)
  else:
    vecs= [getRandomVector(w, n)]
    label="."

  return vecs,label