I need to write a python application with use both of the mysql and sql server is there a general python module or library that can access both mysql and sql server as DBI with perl or should i use 2 libraries and if yes which libraries do you recommend .
I guess you are looking for SQLAlchemy. You will probably need some time getting into it, but it is invaluable once you have covered the basics.
SQLAlchemy acts as a frontend to other, database-specific libraries using the Python DB-API -- but beyond this, it provides a query builder library that abstracts out differences between databases' SQL syntax and permits programmatic query construction while still offering the full power of SQL.
If you are looking for which connection drivers to use, I believe the only one that well work for both [MySQL (driver here) and SQLServer (native to windows/FreeTDS for linux) is pyodbc. @igor has the right idea, though, use SQLAlchemy, you can connect to each database using different engines, but use the same code to interact with both.