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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 normalize(self):

 """
 Makes sure this egg distribution is stored only as an egg file.
 
 The egg file will be created from another existing distribution format
 if needed.
 
 """

        if self.has_egg_file():
            if self.has_zip():
                self.__remove_zip()
        else:
            if self.has_egg_folder():
                if not self.has_zip():
                    self.__zip_egg_folder()
                self.__remove_egg_folder()
            self.__rename_zip_to_egg()