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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 count(cls, iterable):
 """ Returns the number of items in an iterable. """


    iterable = iter(iterable)
    count = 0
    while True:
      try:
        next(iterable)
      except StopIteration:
        break
      count += 1
    return count