If you consistently use the same Data Target and path for all of your files, then I would suggest copying the path from the Browse Data Source's Location field into a text file or clipboard extension for consistent access to the path.
If the data source path is constantly changing, it is currently easier to use the Create Dataset capabilities to start writing your Import UDF with Jupyter:
1. Click Create Dataset
2. Click Import Data Source .
3. Select the Data Target for the storage containing your data source and click BROWSE.
4. Find and select the checkbox for your data source file.
5. Click NEXT.
6. Select the Format: Custom Format and click WRITE PARSER USING JUPYTER.
7. This will open the current Jupyter notebook to a Create Import UDF dialog already populated with the Data Target and path fields.
8. At this point, all you need to do is type in the Module and Function names and click CONFIRM to create your time-saving code snippet that helps you write the UDF.
Thanks for asking this question. I'll also submit a feature request to allow you to browse for Data Source Path from the Jupyter Notebook Create Import UDF modal window.
Glad you're cruising writing import UDFs! Let me know how else I can help with this.