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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 backport(func):
 """ Backport a function name into an old style for compatibility. The docstring is updated to reflect that the new function returned is deprecated and that the other function is preferred. A DeprecationWarning is also raised for using this function. If the script is run with an optimization flag then the real function will be returned without being wrapped. """

    if not __debug__:
        return func

    @_functools.wraps(func)
    def deprecated_function(*args, **kargs):
        _warnings.warn('This function name is deprecated',
                       DeprecationWarning, 2)
        return func(*args, **kargs)
    deprecated_function.__doc__ = None
    return deprecated_function