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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 forces(self, sets_of_forces):
 """Set forces in displacement dataset. Parameters sets_of_forces : array_like A set of atomic forces in displaced supercells. The order of displaced supercells has to match with that in displacement dataset. shape=(displaced supercells, atoms in supercell, 3), dtype='double' ] """


        if 'first_atoms' in self._displacement_dataset:
            for disp, forces in zip(self._displacement_dataset['first_atoms'],
                                    sets_of_forces):
                disp['forces'] = forces
        elif 'forces' in self._displacement_dataset:
            forces = np.array(sets_of_forces, dtype='double', order='C')
            self._displacement_dataset['forces'] = forces