docs: def __write_lipd(dat, usr_path):
      """
      Write LiPD data to file, provided an output directory and dataset name.
  
      :param dict dat: Metadata
      :param str usr_path: Destination path
      :param str dsn: Dataset name of one specific file to write
      :return none:
      """
      global settings
      # no path provided. start gui browse
      if not usr_path:
          # got dir path
          usr_path, _ignore = get_src_or_dst("write", "directory")
      # Check if this is a valid directory path
      valid_path = path_type(usr_path, "directory")
      # If dir path is valid
      if valid_path:
          # Filename is given, write out one file
          if "paleoData" in dat:
              try:
                  if settings["verbose"]:
                      print("writing: {}".format(dat["dataSetName"]))
                  lipd_write(dat, usr_path)
              except KeyError as ke:
                  print("Error: Unable to write file: unknown, {}".format(ke))
              except Exception as e:
                  print("Error: Unable to write file: {}, {}".format(dat["dataSetName"], e))
          # Filename is not given, write out whole library
          else:
              if dat:
                  for name, lipd_dat in dat.items():
                      try:
                          if settings["verbose"]:
                              print("writing: {}".format(name))
                          lipd_write(lipd_dat, usr_path)
                      except Exception as e:
                          print("Error: Unable to write file: {}, {}".format(name, e))
  
      return