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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 in_transaction(connection_name: Optional[str] = None) -> BaseTransactionWrapper: """ Transaction context manager. You can run your code inside ``async with in_transaction():
`` statement to run it into one transaction. If error occurs transaction will rollback. :param connection_name: name of connection to run with, optional if you have only one db connection """

    connection = _get_connection(connection_name)
    return connection._in_transaction()