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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 tuplize(nested):
 """Recursively converts iterables into tuples. Args: nested: A nested structure of items and iterables. Returns: A nested structure of items and tuples. """

  if isinstance(nested, str):
    return nested
  try:
    return tuple(map(tuplize, nested))
  except TypeError:
    return nested