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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 returns_true_or_raises(f):
 """A safety net. Decorator for functions that are only allowed to return True or raise an exception. Args: f: A function whose only expected return value is True. Returns: A wrapped functions whose guaranteed only return value is True. """

    @functools.wraps(f)
    def wrapped(*args, **kwargs):
        ret = f(*args, **kwargs)
        if ret is not True:
            raise RuntimeError("Unexpected return value %r" % ret)
        return True
    return wrapped