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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 _wrap(f):
 """ Wraps a callable `f` in a function that warns that the function is deprecated. """

  def wrapper(*args, **kwargs):
    """
    Issues a deprecation warning and passes through the arguments.
    """
    warnings.warn(str(f) + " is deprecated. Switch to calling the equivalent function in tensorflow. "
                  " This function was originally needed as a compatibility layer for old versions of tensorflow, "
                  " but support for those versions has now been dropped.")
    return f(*args, **kwargs)
  return wrapper