pybind11-dev is available through apt, use this for simplicity

Author: soblin

README.md

@@ -10,7 +10,8 @@ It is supposed to provide the user with almost full access to matplotlib feature
 
 ## Dependencies
 
-- [pybind11](https://github.com/pybind/pybind11) >= 2.9.0
+- [pybind11](https://github.com/pybind/pybind11) >= 2.4.3
+  - `sudo apt install pybind11-dev`
 - compatible with [matplotlib](https://matplotlib.org/stable/index.html) == 3.5.1
 - numpy for `mplot3d`
 - [xtensor](https://github.com/xtensor-stack/xtensor) == 0.24.0 (+ [xtl](https://github.com/xtensor-stack/xtl), for `gallery` demos)