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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 set_title(self, title = None):
 """This method is used to change an entry title. A new title string is needed. """


        if title is None or type(title) is not str:
            raise KPError("Need a new title.")
        else:
            self.title = title
            self.last_mod = datetime.now().replace(microsecond=0)
            return True