A woman looks at traditional Ukrainian Easter eggs “Pysanka”, installed as part of the upcoming celebrations of Easter, in central Kiev, Ukraine, April 29, 2016. A pysanka is a Ukrainian Easter egg, decorated with traditional Ukrainian folk designs using a wax-resist (batik) method. The word pysanka comes from the verb pysaty, “to write”, as the designs are not painted on, but written with beeswax. Many other eastern European ethnic groups decorate eggs using wax resist for Easter. These include the Belarusians, Bulgarians, Croats, Czechs, Hungarians, Lithuanians, Poles, Romanians, Serbs, Slovaks, Slovenes and Sorbs. (Photo by Valentyn Ogirenko/Reuters)

Photographer Andy Hall joins the thousands of fans from west Africa who have gathered for Baaba Maal's annual Blues du Fleuve festival in Senegal. Here: Dancers wait to perform on stage. (Photo by Andy Hall/The Observer)

A Hindu devotee ululates as she holds a banana tree trunk after taking a dip in the waters of the Ganges river during a ritual as part of the Durga Puja festival in Kolkata, India, September 27, 2017. (Photo by Rupak De Chowdhuri/Reuters)

A woman rides a donkey during a donkey race in Roum village, Jizeen countryside, southern Lebanon, August 9, 2015. (Photo by Ali Hashisho/Reuters)

A woman talks to a man as two children play inside a wrecked car at a camp for displaced people in Port-au-Prince, Haiti, March 6, 2016. (Photo by Andres Martinez Casares/Reuters)

A group of dust covered child labourers gather for a portrait in the brick kiln in Kathmandu Valley, Nepal, 22 February 2015. Bleak photos identify the children working their fingers to the bone in Nepalís brick kilns. Photographer Jan Mˆller Hansen documented the conditions of the brick kilns in Kathmandu Valley, Nepal between 2013 and 2016 while he lived and worked in the area. Jan estimates between 150,000 and 175,000 people are employed in the 200 brick kilns littering the Kathmandu Valley. (Photo by Jan Moeller Hansen/Barcroft Images)

Visitors look at an artwork “Hierarchy of Prosperity” created by Indonesian artist Eko Nugroho during the VIP preview of the art fair “Art Basel” in Hong Kong, Tuesday, March 22, 2016. A set of gold-plated metal cubes, tapestries embroidered by unknown North Korean artisans and bales of cardboard waste are among the highlights of the Art Basel Hong Kong fair opening this week. (Photo by Kin Cheung/AP Photo)

Forest guards chase away a rhino that strayed into a residential area after floods forced animals to escape the Kaziranga National park in Nagaon district, in the northeastern state of Assam, August 15, 2017. (Photo by Anuwar Hazarika/Reuters)