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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _group_centroid(mol, ilabels, group_atoms):
 """ Calculate the centroids of a group atoms indexed by the labels of inchi Args: mol: The molecule. OpenBabel OBMol object ilabel: inchi label map Returns: Centroid. Tuple (x, y, z) """

        c1x, c1y, c1z = 0.0, 0.0, 0.0
        for i in group_atoms:
            orig_idx = ilabels[i-1]
            oa1 = mol.GetAtom(orig_idx)
            c1x += float(oa1.x())
            c1y += float(oa1.y())
            c1z += float(oa1.z())
        num_atoms = len(group_atoms)
        c1x /= num_atoms
        c1y /= num_atoms
        c1z /= num_atoms
        return c1x, c1y, c1z