###Answer the question from the input provided. Please answer from input only.

###Input: A fine tribute to the fall of Warsaw and history of Poland can be found in the Warsaw Uprising Museum and in the Katyń Museum which preserves the memory of the crime. The Warsaw Uprising Museum also operates a rare preserved and operating historic stereoscopic theatre, the Warsaw Fotoplastikon. The Museum of Independence preserves patriotic and political objects connected with Poland's struggles for independence. Dating back to 1936 Warsaw Historical Museum contains 60 rooms which host a permanent exhibition of the history of Warsaw from its origins until today.

The 17th century Royal Ujazdów Castle currently houses Centre for Contemporary Art, with some permanent and temporary exhibitions, concerts, shows and creative workshops. The Centre currently realizes about 500 projects a year. Zachęta National Gallery of Art, the oldest exhibition site in Warsaw, with a tradition stretching back to the mid-19th century organises exhibitions of modern art by Polish and international artists and promotes art in many other ways. Since 2011 Warsaw Gallery Weekend is held on last weekend of September.

Their local rivals, Polonia Warsaw, have significantly fewer supporters, yet they managed to win Ekstraklasa Championship in 2000. They also won the country’s championship in 1946, and won the cup twice as well. Polonia's home venue is located at Konwiktorska Street, a ten-minute walk north from the Old Town. Polonia was relegated from the country's top flight in 2013 because of their disastrous financial situation. They are now playing in the 4th league (5th tier in Poland) -the bottom professional league in the National – Polish Football Association (PZPN) structure.

The mermaid (syrenka) is Warsaw's symbol and can be found on statues throughout the city and on the city's coat of arms. This imagery has been in use since at least the mid-14th century. The oldest existing armed seal of Warsaw is from the year 1390, consisting of a round seal bordered with the Latin inscription Sigilium Civitatis Varsoviensis (Seal of the city of Warsaw). City records as far back as 1609 document the use of a crude form of a sea monster with a female upper body and holding a sword in its claws. In 1653 the poet Zygmunt Laukowski asks the question:

The origin of the legendary figure is not fully known. The best-known legend, by Artur Oppman, is that long ago two of Triton's daughters set out on a journey through the depths of the oceans and seas. One of them decided to stay on the coast of Denmark and can be seen sitting at the entrance to the port of Copenhagen. The second mermaid reached the mouth of the Vistula River and plunged into its waters. She stopped to rest on a sandy beach by the village of Warszowa, where fishermen came to admire her beauty and listen to her beautiful voice. A greedy merchant also heard her songs; he followed the fishermen and captured the mermaid.



###Question: What did Artur Oppman give to the world?

###Answer: {'answer':'legend'}