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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 __load_countries(self, db):
 """Load the list of countries"""


        try:
            countries = self.__read_countries_file()
        except IOError as e:
            raise LoadError(str(e))

        try:
            with db.connect() as session:
                for country in countries:
                    session.add(country)
        except Exception as e:
            raise LoadError(str(e))