People stand under a giant Czech flag as they arrive to light candles at the base of a statue of St. Wenceslas to commemorate the death of former Czech President Vaclav Havel on December 18, 2011 in Prague, Czech Republic. Havel, who led the Velvet Revolution that forced communist rule in Czechoslovakia to crumble in 1989, died in the early morning today in his sleep at the age of 75. (Photo by Sean Gallup/Getty Images)

General view of a herbal store in Cairo, Egypt January 10, 2017. In an economic crisis that has led to a shortage of medicines, Egyptians are skipping trips to drug stores and instead turning to herbal remedies to treat every-day illnesses. (Photo by Mohamed Abd El Ghany/Reuters)

Their Royal Highnesses Prince William, Duke of Cambridge and Catherine, Duchess of Cambridge kiss on the balcony at Buckingham Palace on April 29, 2011 in London, England. The marriage of the second in line to the British throne was led by the Archbishop of Canterbury and was attended by 1900 guests, including foreign Royal family members and heads of state. Thousands of well-wishers from around the world have also flocked to London to witness the spectacle and pageantry of the Royal Wedding. (Photo by Peter Macdiarmid/Getty Images)

An autumn leaf sticks to a bench near the Bishops Castle near Wells Cathedral on November 1, 2011 in Wells, England. According to a number of nature watchers the autumn colours are currently reaching their peak following an unusually warm September and October which has led to trees holding onto their leaves longer than normal. (Photo by Matt Cardy/Getty Images)

“Ой, да не вечер” – the Russian national song. It is also known under the name “Stepan Razin's Dream”. It is sung on behalf of Cossack Stepan Razin ((1630–1671) was a Cossack leader who led a major uprising against the nobility and Tsar's bureaucracy in South Russia) who tells the bad dream foretelling trouble. Sings: Pelagea Sergeevna Efimova (born 14.06.1986 in Novosibirsk, Russia).

Cowboys Wyatt Williams (R) and David Thompson work to restrain a calf in order to give it medicine near Ignacio, Colorado June 12, 2014. The land where the cattle graze is leased from the Forest Service by third-generation rancher Steve Pargin. Several times a year, he and a crew led by his head cowboy, David Thompson, spend a week or more herding cattle from mountain range to mountain range to prevent them from causing damage to fragile ecosystems by staying in a single area too long. (Photo by Lucas Jackson/Reuters)

Opposition students march against Venezuelan President Nicolas Maduro's government in Caracas February 12, 2015. Venezuelan troops blocked students during marches against Maduro on Thursday as pro-government supporters also rallied on the anniversary of 2014 protests that led to 43 deaths. In Caracas, troops cordoned off scores of students on an unauthorized march to a church where they planned a mass in honour of demonstrators who died. (Photo by Jorge Silva/Reuters)

In this Tuesday, March 17, 2015 photo, a French military plane takes off from the flight deck of the French Navy aircraft carrier Charles de Gaulle in the Persian Gulf. Aircraft aboard the French carrier are flying bombing and reconnaissance missions as part of a U.S.-led coalition targeting Islamic State militants in Iraq. (Photo by Hasan Jamali/AP Photo)