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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 pymatgen_mol(self):
 """ Returns pymatgen Molecule object. """

        sp = []
        coords = []
        for atom in ob.OBMolAtomIter(self._obmol):
            sp.append(atom.GetAtomicNum())
            coords.append([atom.GetX(), atom.GetY(), atom.GetZ()])
        return Molecule(sp, coords)