What is the first line of a Databricks Python notebook when viewed in a text editor?

In a Databricks Python notebook, when you view the notebook in a text editor, the first line is a comment that starts with a hash symbol followed by the text "Databricks notebook source." This is indicative of how Databricks represents notebooks in a text format, where Python code and markdown cells are typically structured as comments to provide context and specify the content type.

The presence of the hash symbol indicates that this line is a comment, and hence, it is meant for the reader rather than for execution as code. This mechanism helps in identifying the cells of the notebook and the nature of their contents, particularly when the notebook is converted to formats like HTML or Markdown. The comment line effectively marks the commencement of the Databricks-specific format used to encapsulate the notebook's content.

Understanding this structure is important because it highlights how Databricks maintains compatibility and readability for various types of content within the notebook environment, allowing users to easily identify the organization and structure of their code and markdown cells.