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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 get_pymatgen_molecule(self):
 """Create a Molecule instance of the pymatgen library .. warning:: The `pymatgen library <http://pymatgen.org>`_ is imported locally in this function and will raise an ``ImportError`` exception, if it is not installed. Args: None Returns: :class:`pymatgen.core.structure.Molecule`: """

        from pymatgen import Molecule
        return Molecule(self['atom'].values,
                        self.loc[:, ['x', 'y', 'z']].values)