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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 tostream(func, module_name=None):
 """ Decorator to convert the function output into a Stream. Useful for generator functions. Note ---- Always use the ``module_name`` input when "decorating" a function that was defined in other module. """

  @wraps(func)
  def new_func(*args, **kwargs):
    return Stream(func(*args, **kwargs))
  if module_name is not None:
    new_func.__module__ = module_name
  return new_func