docs: def __convert_none_to_zero(self, ts):
          """
          Convert None values to 0 so the data works with Matplotlib
          :param ts:
          :return: a list with 0s where Nones existed
          """
  
          if not ts:
              return ts
  
          ts_clean = [val if val else 0 for val in ts]
  
          return ts_clean