It’s funny how programmers get in a "rut", using the same old coding habits and command line syntax for years on end. I just found that you can create new directories and subdirectories with a single Unix mkdir command using the -p parm.
mkdir -p top_level_directory/child_directory/another_child_directory
And if you’re curious, this won’t work (I tried it):
mkdir -p onemoredir/../anotherdir
Goes to show you that we should follow the same advice we give the junior developers – "check the man page".