DataMigration py conf (Azure#2553)

specification/datamigration/resource-manager/readme.md

@@ -61,6 +61,7 @@ This is not used by Autorest itself.
 
 ``` yaml $(swagger-to-sdk)
 swagger-to-sdk:
+  - repo: azure-sdk-for-python
   - repo: azure-sdk-for-go
 ```
 
@@ -81,14 +82,29 @@ csharp:
 ## Python
 
 These settings apply only when `--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>`.
+Use `--python-mode=update` if you already have a setup.py and just want to update the code itself.
 
 ``` yaml $(python)
+python-mode: create
 python:
   azure-arm: true
-  output-folder: $(output-folder)Generated/Python
   license-header: MICROSOFT_MIT_NO_VERSION
   payload-flattening-threshold: 2
   namespace: azure.mgmt.datamigration
+  package-name: azure-mgmt-datamigration
+  package-version: 0.1.0
+  clear-output-folder: true
+```
+``` yaml $(python) && $(python-mode) == 'update'
+python:
+  no-namespace-folders: true
+  output-folder: $(python-sdks-folder)/azure-mgmt-datamigration/azure/mgmt/datamigration
+```
+``` yaml $(python) && $(python-mode) == 'create'
+python:
+  basic-setup-py: true
+  output-folder: $(python-sdks-folder)/azure-mgmt-datamigration
 ```
 
 ## Go