code: def init(self):
          
  
          evclass_shape = [16, 40, 10]
          evtype_shape = [16, 16, 40, 10]
          evclass_psf_shape = [16, 40, 10, 100]
          evtype_psf_shape = [16, 16, 40, 10, 100]
  
          self._hists_eff = dict()
          self._hists = dict(evclass_on=np.zeros(evclass_shape),
                             evclass_off=np.zeros(evclass_shape),
                             evclass_alpha=np.zeros([16, 40, 1]),
                             evtype_on=np.zeros(evtype_shape),
                             evtype_off=np.zeros(evtype_shape),
                             evtype_alpha=np.zeros([16, 1, 40, 1]),
                             evclass_psf_on=np.zeros(evclass_psf_shape),
                             evclass_psf_off=np.zeros(evclass_psf_shape),
                             evtype_psf_on=np.zeros(evtype_psf_shape),
                             evtype_psf_off=np.zeros(evtype_psf_shape),
                             )
docs: Initialize histograms.