docs: def is_mdgel(self):
          """File has MD Gel format."""
          # TODO: this likely reads the second page from file
          try:
              ismdgel = self.pages[0].is_mdgel or self.pages[1].is_mdgel
              if ismdgel:
                  self.is_uniform = False
              return ismdgel
          except IndexError:
              return False