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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 fresh_transaction(self, name=None):
 """On entrance to this context manager, hold an exclusive lock and create a fresh transaction for redshift, then commit and begin a new one before releasing the lock on exit. See drop_relation in RedshiftAdapter for more information. :param Optional[str] name: The name of the connection to use, or None to use the default. """

        with drop_lock:

            connection = self.get_thread_connection()

            if connection.transaction_open:
                self.commit()

            self.begin()
            yield

            self.commit()
            self.begin()