Given a photon dropping from $\lambda_1$ to $\lambda_2$, its energy will drop from $\frac{hc}{(\lambda_1)}$ to $\frac{hc}{(\lambda_2)}$. However, I was wondering if there is any significance in the energy of the change in wavelength itself. For $\Delta \lambda = \lambda_2 - \lambda_1$, this change in wavelength has an energy $\frac{hc}{(\Delta \lambda)}$, yet this value does not correspond at all (as far as I can see) with $\Delta E = \frac{hc}{(\lambda_1)} -\frac{hc}{(\lambda_2)}$. Is this just a subtlety in the math, or is there actually meaning behind the value $\frac{hc}{(\Delta \lambda)}$?


Question: Are programming books in other languages useful for Python?
Answer: Absolutely! It's actually very helpful to break away from your primary language occasionally because this lets you see programming concepts through a different lens which will allow you to gain new perspectives. 

What makes any software good, or high quality is never about the syntax or language of choice.  It's how that language is applied. Steve McConnell calls this programming into a language instead of programming in a language. 

McConnell wrote Code Complete, a book I highly recommend. He makes a specific note why the examples are in many different languages. One of the reasons is he wants the reader to focus on the concepts he is illustrating and not on the syntax.

The books in your list describes general concepts that would certainly be useful to any programmer, regardless of their language of choice.

Starting out you do want to focus on just being able to write code that compiles. It doesn't take very long to learn the syntax of a given language and with documentation and intellisense this takes even more away from how much you have to actually remember. Most languages can be learned within a few months. However, writing high quality software is a discipline and craftsmanship that takes years of practice and experience and even then there will always be room for improvement. Learning about design concepts such as how to make your software more testable, modular, loosely coupled etc. will open your eyes on how you look at code in general.

When you stop caring about syntax and can see code through a neutral lens then this will truly benefit you as a programmer.