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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_menu_separator(self, img):
 """Sets the menu separator. Must be called before adding entries to the menu """

        if img:
            self.menu_separator_tag = '<img src="{}" alt="/" />'.format(
                self._rel(img))
        else:
            self.menu_separator_tag = None