Hello, I upgraded ASE from version 3.20.0b1 to 3.23.0b1 With 3.20.0b1, I was able to read and write POSCAR with selective dynamics but now I am able to add constraints to ASE atoms but writing to POSCAR gives out an error. Here is a simple reproducible example for reading a POSCAR. For example: from ase.io.vasp import read_vasp atoms = read_vasp(‘POSCAR’) The POSCAR file is a…