How to setup a simple bazel build action from scratch

In this video I'm going through some of the things I have recently learned about setting up external, executable dependencies using Bazel. - We create a custom build rule - We pass simple data (string) into the rule - We pass more complex data (standalone python executable) - We pass a file into the rule We then use all of these arguments to create a simple build action that ends up writing a string to a file.