Add new client to retrieve exportable .ipynb of current session.

http://b/171318603

Author: rosbo

Dockerfile

@@ -488,6 +488,7 @@ RUN echo "deb [signed-by=/usr/share/keyrings/cloud.google.gpg] http://packages.c
 ENV PYTHONUSERBASE "/root/.local"
 ADD patches/kaggle_gcp.py /root/.local/lib/python3.7/site-packages/kaggle_gcp.py
 ADD patches/kaggle_secrets.py /root/.local/lib/python3.7/site-packages/kaggle_secrets.py
+ADD patches/kaggle_session.py /root/.local/lib/python3.7/site-packages/kaggle_session.py
 ADD patches/kaggle_web_client.py /root/.local/lib/python3.7/site-packages/kaggle_web_client.py
 ADD patches/kaggle_datasets.py /root/.local/lib/python3.7/site-packages/kaggle_datasets.py
 ADD patches/log.py /root/.local/lib/python3.7/site-packages/log.py

patches/kaggle_session.py

@@ -0,0 +1,26 @@
+"""
+This library adds support for retrieving data related to the current user session.
+"""
+
+import os
+
+from kaggle_web_client import KaggleWebClient
+
+
+class UserSessionClient():
+    GET_SOURCE_ENDPOINT = '/requests/GetKernelRunSourceForCaipRequest'
+
+    def __init__(self):
+        self.web_client = KaggleWebClient()
+
+    def get_exportable_ipynb(self):
+        """Fetch the .ipynb source of the current notebook session.
+        
+        If Kaggle datasets are attached to the notebook, the source will
+        include an additonnal cell with logic to download the datasets
+        outside the Kaggle platform.
+        """
+        request_body = {
+            'UseDraft': True,        
+        }
+        return self.web_client.make_post_request(request_body, self.GET_SOURCE_ENDPOINT)