postgresql readme t2 config (Azure#14067)

Author: RAY-316

specification/postgresql/resource-manager/readme.python.md

@@ -9,6 +9,7 @@ These settings apply only when `--track2` is specified on the command line.
 azure-arm: true
 license-header: MICROSOFT_MIT_NO_VERSION
 package-name: azure-mgmt-rdbms
+package-version: 1.0.0b1
 no-namespace-folders: true
 ```
 
@@ -21,9 +22,20 @@ clear-output-folder: true
 batch:
   - tag: package-2020-01-01
   - tag: package-2020-11-05-preview
+  - tag: package-2021-03-31-privatepreview
 ```
 
 
+### Tag: package-2021-03-31-privatepreview and python
+
+These settings apply only when `--tag=package-2021-03-31-privatepreview --python` is specified on the command line.
+Please also specify `--python-sdks-folder=<path to the root directory of your azure-sdk-for-python clone>`.
+
+``` yaml $(tag) == 'package-2021-03-31-privatepreview' && $(python)
+namespace: azure.mgmt.rdbms.postgresql
+output-folder: $(python-sdks-folder)/rdbms/azure-mgmt-rdbms/azure/mgmt/rdbms/postgresql
+```
+
 ### Tag: package-2020-01-01 and python
 
 These settings apply only when `--tag=package-2020-01-01 --python` is specified on the command line.