download_CoLChina       Download 'Catalogue of Life China': Annual
                        Checklist
get_province            Statistics on Species or Infraspecies by
                        Province
get_top20               Download the top20 species
list_df                 Lists convert data frame
open_URL                Opening the web pages with query
search_checklist        Search checklist
search_familyID         Search family IDs
search_taxonID          Search taxon IDs
