Changes in version 0.2.2                        

  - Corrected the region code of Danzhou (儋州市) from 469003 to 460400 for
    the years 2015–2022, reflecting its 2015 upgrade from a
    provincially-administered county-level city to a prefecture-level
    city (#55).
  - Renamed the city-rank columns for 2020–2022 from 2020_cityranking /
    2021_cityrankin / 2022_cityranking to 2020_rank / 2021_rank /
    2022_rank, fixing a typo in the 2021 column name and aligning the
    naming convention with earlier years so that convert_to = "rank"
    works for 2020–2022 (#51).

                 Changes in version 0.2.1 (2026-04-07)                  

  - Fixed the to_pinyin function
  - Fixed the incomplete_name function

                 Changes in version 0.2.0 (2025-07-05)                  

  - Updated the code to assign province‘s name to a city based on the
    year
  - Added more data like Yunnan and Guizhou
  - Extended the year range to 2022
  - Fixed some data errors
  - Vectorized the merging functions
  - Corrected the region codes of Xinjiang

                 Changes in version 0.1.2 (2024-03-10)                  

  - New function rank for level of cities
  - New method in incomplete_name so that the function can deal with
    input with only part of incomplete region names
  - Bug fix
      - present Shaanxi, tibet, macao, hongkong, inner_mongolia
        correctly
      - full name of "Ning Xia"
      - Correct name of Xinjiang

                 Changes in version 0.1.1 (2021-08-02)                  

  - Styled function with tidyverse style
  - Rewrote method  as convert_to
  - Rewrote incompleteName as incomplete_name
  - Rewrote language_region and language_trans as to_dialect
  - Simplified the codes.
  - Added more detailed warning messages.

                        Changes in version 0.0.9                        

  - Enable to provincial-level conversion with province
  - Fixed the error of incompleteName
  - Simplified the codes.
  - Add parameter topinyin & method "2area"
  - Remove unnecessary warning about 'code2code'
  - Fix the bug in language_region