code: def compute_ring_center(mol, ring_indices):
      """Computes 3D coordinates of a center of a given ring.
  
      Parameters:
      -----------
      mol: rdkit.rdchem.Mol
          Molecule containing a ring
      ring_indices: array-like
          Indices of atoms forming a ring
  
      Returns:
      --------
      ring_centroid: np.ndarray
          Position of a ring center
      """
      conformer = mol.GetConformer()
      ring_xyz = np.zeros((len(ring_indices), 3))
      for i, atom_idx in enumerate(ring_indices):
          atom_position = conformer.GetAtomPosition(atom_idx)
          ring_xyz[i] = np.array(atom_position)
      ring_centroid = compute_centroid(ring_xyz)
      return ring_centroid
  
imports: import os
  import logging
  import itertools
  import numpy
  from io import StringIO
  from deepchem.utils.pdbqt_utils import pdbqt_to_pdb
  from deepchem.utils.pdbqt_utils import convert_mol_to_pdbqt
  from deepchem.utils.pdbqt_utils import convert_protein_to_pdbqt
  from deepchem.utils.geometry_utils import compute_pairwise_distances
  from deepchem.utils.geometry_utils import compute_centroid
  from deepchem.utils.fragment_utils import MolecularFragment
  from deepchem.utils.fragment_utils import MoleculeLoadException
  from typing import Any, List, Sequence, Tuple, Set, Optional, Dict, Union
  from deepchem.utils.typing import OneOrMany, RDKitMol
label_desc: Use image node_id 14 for calling a global function with example usage: compute_ring_center(mol, ring_indices) and returns: ring_centroid