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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 create(self, db_name, **kwargs):
 """ Construct a PostgresDatabase and create it on self """

        db = PostgresDatabase(
            db_name, host=self.host, port=self.port,
            superuser=self.superuser, **kwargs)
        db.ensure_user()
        db.create()
        return db