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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 database_path(self):
 """ Full database path. Includes the default location + the database filename. """

        filename = self.database_filename
        db_path = ":memory:" if filename == ":memory:" else (
            path.abspath(path.join(__file__, "../..", "..", "data", filename)))
        return db_path