code: def cell_styles(self):
          
          styles = {}
          for colname, col in self.dataframe.items():
              for rowname, value in col.items():
                  if isinstance(value, Value) and value.style is not None:
                      style = value.style
                      if not isinstance(style, CellStyle):
                          style = self._named_styles[style]
                      styles[(rowname, colname)] = style
          return styles
docs: dict of {(row name, col name): style}