Comparing many maths fonts [closed]

Question

I'd like to produce a document comparing all of the different bb (blackboard bold) fonts available in LaTeX. symbols-a4.pdf gives is what I will assume is a comprehensive list:

The problem is that three different packages override the \mathbb command. I tried to 'save' each version as shown in the following MWE, but to no avail:

\documentclass{article}
\usepackage{bbold}
\let\bboldbb\mathbb
\usepackage{amsfonts}
\let\amsbb\mathbb

\begin{document}
$\amsbb{N} \bboldbb{N}$
\end{document}

Using \def in place of \let doesn't work either. How can I use multiple versions of \mathbb at once? (And what is wrong with my MWE?)