code: def get_column(self, col):
          
          # catch corner case with an empty file (group with no datasets)
          if not len(self.group.keys()):
              return np.array([])
          vals = self.group[col]
          if self.filter_func:
              return vals[self.mask]
          else:
              return vals[:]
docs: Parameters
          ----------
          col : string
              Name of the dataset to be returned
  
          Returns
          -------
          numpy array
              Values from the dataset, filtered if requested