docs: def _format_list(self, data):
          """
          Format a list to use in javascript
          """
          dataset = "["
          i = 0
          for el in data:
              if pd.isnull(el):
                  dataset += "null"
              else:
                  dtype = type(data[i])
                  if dtype == int or dtype == float:
                      dataset += str(el)
                  else:
                      dataset += '"' + el + '"'
              if i < len(data) - 1:
                  dataset += ', '
          dataset += "]"
          return dataset