docs: def create_legend(info, c, option="clean", use_index=False):
      """creating more informative legends"""
  
      logging.debug("    - creating legends")
      mass, loading, label = info.loc[c, ["masses", "loadings", "labels"]]
  
      if use_index or not label:
          label = c.split("_")
          label = "_".join(label[1:])
  
      if option == "clean":
          return label
  
      if option == "mass":
          label = f"{label} ({mass:.2f} mg)"
      elif option == "loading":
          label = f"{label} ({loading:.2f} mg/cm2)"
      elif option == "all":
          label = f"{label} ({mass:.2f} mg) ({loading:.2f} mg/cm2)"
  
      return label