Example that will throw a "ValueError: Bad conformer id" with RDKit

bad_conformer_id.py

import sys

from rdkit import Chem
from rdkit.Chem import AllChem

if __name__ == "__main__":

    # my_smiles = ['C#N', 'C1C(C2C1OC2)O', 'C1C2C3C1C2C3O', 'C1C2COC2C1O', 'C1CC2(C1CC2)O',
    #              'C1CC2(C1NC2)O', 'C1CC2(C1OC2)N', 'C1CC2(C1OC2)O', 'C1CC2C1CC2O']
    my_smiles = ['C#N', 'C1C(C2C1OC2)O']

    for smiles in my_smiles:

        mol = Chem.MolFromSmiles(smiles)
        mol = Chem.AddHs(mol)
        AllChem.EmbedMolecule(mol, useRandomCoords=True)


        AllChem.EmbedMultipleConfs(mol,
                numConfs=50,
                # useExpTorsionAnglePrefs=True,
                # useBasicKnowledge=True,
                # enforceChirality=True
            )   

        optimization = AllChem.MMFFOptimizeMoleculeConfs(mol, maxIters=100)

        for i,conf in enumerate(mol.GetConformers()):

            filename = "output_%02i_%s.sdf" % (i, smiles)

            tm = Chem.Mol(mol, False, conf.GetId())
            writer = Chem.SDWriter(filename)
            writer.write(tm)
            
            

thank you so much!!!!