docs: def get_qpimage(self, idx=0):
          """Return background-corrected QPImage"""
          if self._bgdata:
              # The user has explicitly chosen different background data
              # using `get_qpimage_raw`.
              qpi = super(SingleHdf5Qpimage, self).get_qpimage()
          else:
              # We can use the background data stored in the qpimage hdf5 file
              qpi = qpimage.QPImage(h5file=self.path,
                                    h5mode="r",
                                    h5dtype=self.as_type,
                                    ).copy()
              # Force meta data
              for key in self.meta_data:
                  qpi[key] = self.meta_data[key]
              # set identifier
              qpi["identifier"] = self.get_identifier(idx)
          return qpi