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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 output_str(f):
 """Create a function that always return instances of `str`. This decorator is useful when the returned string is to be used with libraries that do not support ̀`unicode` in Python 2, but work fine with Python 3 `str` objects. """

    if six.PY2:
        #@functools.wraps(f)
        def new_f(*args, **kwargs):
            return f(*args, **kwargs).encode("utf-8")
    else:
        new_f = f
    return new_f