Driver library is used to create business strategy associated with departments and project impacts.
Here below is the given code to create Driver Library using PSI.
First I am exporting Driver Library data from one environment and then importing data into another environment.

Exporting: Use export environment credentials

DriverWebSvc.DriverDataSet driverDataSet = new DriverWebSvc.DriverDataSet();

// Read the list of drivers.
DriverWebSvc.DriverDataSet driverList = driverWebSvc.ReadDriverList();

foreach (DriverWebSvc.DriverDataSet.DriverRow driverRow in driverList.Driver.Rows)
{
	DriverWebSvc.DriverDataSet driverDataSetTemp = driverWebSvc.ReadDriver(driverRow.DRIVER_UID);

	// Merging Driver data table
	driverDataSet.Driver.Merge(driverDataSetTemp.Driver);

	// Merging DriverImpactStatements data table
	driverDataSet.DriverImpactStatements.Merge(driverDataSetTemp.DriverImpactStatements);

	// Merging DriverDepartments data table
	driverDataSet.DriverDepartments.Merge(driverDataSetTemp.DriverDepartments);
}

Importing: Use import environment credentials

DriverWebSvc.DriverDataSet targetDriverDataSet = driverWebSvc.ReadDriverList();
//Deleting existing driver library from environment
List<Guid> driverUids = new List<Guid>();
foreach (DriverDataSet.DriverRow driverRow in targetDriverDataSet.Driver.Rows)
{
	driverUids.Add(driverRow.DRIVER_UID);
}

if (driverUids.Count > 0)
	driverWebSvc.DeleteDrivers(driverUids.ToArray());

foreach (DriverDataSet.DriverRow driverRow in driverDataSet.Driver.Rows)
{
	try
	{
		DriverWebSvc.DriverDataSet drvDS = new DriverWebSvc.DriverDataSet();

		//Adding Driver row
		drvDS.Driver.Rows.Add(driverRow.ItemArray);

		// Adding Driver Impact Statements row
		foreach (DriverDataSet.DriverImpactStatementsRow driverImpactStatementsRow in driverDataSet.DriverImpactStatements.Rows)
		{
			if (driverImpactStatementsRow.DRIVER_UID == driverRow.DRIVER_UID)
			{
				drvDS.DriverImpactStatements.Rows.Add(driverImpactStatementsRow.ItemArray);
			}
		}

		// Adding Driver Impact Statements row
		foreach (DriverDataSet.DriverDepartmentsRow driverDepartmentsRow in driverDataSet.DriverDepartments.Rows)
		{
			if (driverDepartmentsRow.DRIVER_UID == driverRow.DRIVER_UID)
			{
				drvDS.DriverImpactStatements.Rows.Add(driverDepartmentsRow.ItemArray);
			}
		}

		driverWebSvc.CreateDriver((DriverWebSvc.DriverDataSet)drvDS);
		successfulRecords++;
	}
	catch (SoapException sEx)
	{
		//log exception
	}
	catch (Exception ex)
	{
		//log exception
	}

}

Hope this code will help you.Thanks