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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 dataset(self, dataset):
 """Set dataset having displacements and optionally forces Note ---- Elements of the list accessed by 'first_atoms' corresponds to each displaced supercell. Each displaced supercell contains only one displacement. dict['first_atoms']['forces'] gives atomic forces in each displaced supercell. Parameters displacement_dataset : dict There are two dict structures. Type 1. One atomic displacement in each supercell: {'natom': number of atoms in supercell, 'first_atoms': [ {'number': atom index of displaced atom, 'displacement': displacement in Cartesian coordinates, 'forces': forces on atoms in supercell}, Type 2. All atomic displacements in each supercell: {'natom': number of atoms in supercell, 'displacements': ndarray, dtype='double', order='C', shape=(supercells, natom, 3) 'forces': ndarray, dtype='double',, order='C', shape=(supercells, natom, 3)} In type 2, displacements and forces can be given by numpy array with different shape but that can be reshaped to (supercells, natom, 3). """


        if 'displacements' in dataset:
            natom = self._supercell.get_number_of_atoms()
            if type(dataset['displacements']) is np.ndarray:
                if dataset['displacements'].ndim in (1, 2):
                    d = dataset['displacements'].reshape((-1, natom, 3))
                    dataset['displacements'] = d
            if type(dataset['forces']) is np.ndarray:
                if dataset['forces'].ndim in (1, 2):
                    f = dataset['forces'].reshape((-1, natom, 3))
                    dataset['forces'] = f
        self._displacement_dataset = dataset
        self._supercells_with_displacements = None