Update Raspbian OS on the Raspberry Pi

I have an early Raspberry Pi model running the Raspbian OS "jessie" release (which lacks Python 3.6 and its useful "f-string" format syntax.) So, I wanted to upgrade to the contemporary "buster" release to resolve that issue. Here's what worked:

1. Follow these excellent instructions (Use the section "Update Raspbian to the Latest Version") to manually update OS releases sequentially. So, in my case, I upgraded from "jessie" to "stretch" and then from "stretch" to "buster."
2. You'll likely want to upgrade the Docker packages, too. To do it, refer to the following steps:
   
• Remove the existing Docker installation (See "Uninstall old versions.")
  
• Download and run the "Convenience Script" (See "Install using the convenience script") to do the upgrade installation.

Now, "You're Good to Go" with the latest release ("buster" in this example!) Enjoy 😀👍