code: def kvectors(self, norm=False, form='broadcast', real=False, shift=False):
          
          if norm is False:
              norm = 1
          if norm is True:
              norm = np.array(self.shape)
          norm = aN(norm, self.dim, dtype='float')
  
          v = list(np.fft.fftfreq(self.shape[i])/norm[i] for i in range(self.dim))
  
          if shift:
              v = list(np.fft.fftshift(t) for t in v)
  
          if real:
              v[-1] = v[-1][:(self.shape[-1]+1)//2]
  
          return self._format_vector(v, form=form)
docs: Return the kvectors associated with this tile, given the standard form
          of -0.5 to 0.5. `norm` and `form` arguments arethe same as that passed to
          `Tile.coords`.
  
          Parameters
          -----------
          real : boolean
              whether to return kvectors associated with the real fft instead