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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 db_conn(self):
 """Create a temporary in memory DB and return the connection."""

        if self._db_conn is None:
            try:
                self._db_conn = sqlite3.connect(':memory:')
            except sqlite3.Error as e:
                self.handle_error(e)
        return self._db_conn