The moon is seen behind a hammer and sickle, parts of the sculpture of "Worker and Kolkhoz Woman," in Moscow, Russia May 7, 2020. REUTERS/Maxim Shemetov

A man wearing a hat with hammer and a sickle sign attends a demonstration against the government's pensions reform bill during a nationwide strike in Paris, France February 20, 2020. REUTERS/Pascal Rossignol

Yang Junhao pulls a bamboo stem down after chopping it off with a sickle, on a hill at the AnotherCommunity in Guanzhong village, Fuzhou, Fujian province, China, October 31, 2019. REUTERS/Tingshu Wang SEARCH "CHINA COMMUNE" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

Chhaya Kharade, 36, an unemployed farm labourer poses with her sickle inside her house in Chincholi, India, March 12, 2019. Picture taken March 12, 2019. To match Insight INDIA-ELECTION/WOMEN-JOBS REUTERS/Danish Siddiqui

Dr. Matthew Hsieh, Dr. John Tisdale and Lynndrick Holmes discuss Holmes' recovery from sickle cell anemia after participating in Tisdale's clinical trial at the National Institute of Health's Clinical Center in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. Matthew Hsieh, Dr. John Tisdale and Lynndrick Holmes discuss Holmes' recovery from sickle cell anemia after participating in Tisdale's clinical trial at the National Institute of Health's Clinical Center in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Lynndrick Holmes, 29, walks with Dr. John Tisdale through the National Institute of Health's Clinical Center after the agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. Holmes has shown significant recovery from the disease after participating in Tisdale's clinical trial. REUTERS/Erin Scott

Lynndrick Holmes, 29, walks with Dr. John Tisdale through the National Institute of Health's Clinical Center after the agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. Holmes has shown significant recovery from the disease after participating in Tisdale's clinical trial. REUTERS/Erin Scott

Lynndrick Holmes, 29, discusses his recovery from sickle cell anemia after participating in Dr. John Tisdale's clinical trial at the National Institute of Health's Clinical Center in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Lynndrick Holmes, 29, discusses his recovery from sickle cell anemia after participating in Dr. John Tisdale's clinical trial at the National Institute of Health's Clinical Center in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Lynndrick Holmes, 29, discusses his recovery from sickle cell anemia after participating in Dr. John Tisdale's clinical trial at the National Institute of Health's Clinical Center in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

A researcher works in Dr. John Tisdale's lab at the National Institutes of Health after the agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. John Tisdale speaks with a researcher in his lab at the National Institutes of Health after the agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. John Tisdale speaks with one of his a lab assistants at the National Institutes of Health after the agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. John Tisdale discusses his work for the National Institute of Health's breakthrough in sickle cell anemia research during an interview in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. John Tisdale discusses his work for the National Institute of Health's breakthrough in sickle cell anemia research during an interview in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

Dr. John Tisdale discusses his work for the National Institute of Health's breakthrough in sickle cell anemia research during an interview in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins discusses his agency's breakthrough in sickle cell anemia research during an interview in Washington, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins discusses his agency's breakthrough in sickle cell anemia research during an interview in Washington, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins poses for a portrait after his agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins poses for a portrait after his agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins poses for a portrait after his agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins poses for a portrait after his agency announced a breakthrough in sickle cell anemia research in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

National Institutes of Health Director Francis Collins discusses his agency's breakthrough in sickle cell anemia research during an interview in Bethesda, U.S. March 11, 2019. REUTERS/Erin Scott

U.S. first lady Melania Trump receives a bouquet of roses from 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump works with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump makes candygrams with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump gets a hug while making candygrams with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump gets a hug while making candygrams with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump makes candygrams with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

U.S. first lady Melania Trump makes candygrams with 13-year-old sickle cell disease sufferer Amani, of Mombasa, Kenya, during a Valentine’s Day visit with young patients at the Children's Inn at the National Institutes of Health (NIH) in Bethesda, Maryland, U.S., February 14, 2019. Amani is preparing for a bone marrow transplant. REUTERS/Jonathan Ernst

An artisan places an artificial sickle on an idol of Hindu goddess Kali inside a pandal, or a temporary platform, on the occasion of Kali Puja festival in Kolkata, India, November 6, 2018. REUTERS/Rupak De Chowdhuri TPX IMAGES OF THE DAY

An artisan places an artificial sickle on an idol of Hindu goddess Kali inside a pandal, or a temporary platform, on the occasion of Kali Puja festival in Kolkata, India, November 6, 2018. REUTERS/Rupak De Chowdhuri

Sickles, displayed for sale, hang at a workshop in Peshawar, Pakistan April 27, 2018. REUTERS/Fayaz Aziz

A newly made crossbow is seen at a workshop in Liuku township of Nujiang Lisu Autonomous Prefecture in Yunnan province, China, March 27, 2018. REUTERS/Aly Song SEARCH "SONG CROSSBOW" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

A Russian state flag is lowered at half-mast on the day of national mourning for the victims of a shopping mall fire in Kemerovo, with the coat of arms of the Soviet Union seen on the facade of the building of the lower house of parliament, State Duma, in central Moscow, Russia March 28, 2018. REUTERS/Sergei Karpukhin

A supporter is seen thorough the flag of Communist Party of India (Marxist) CPI (M) during a protest against what they say is an anti-people budget, after India’s Finance Minister Arun Jaitley presented the federal budget in the Indian parliament last week, in New Delhi, India, February 5, 2018. REUTERS/Adnan Abidi

Product Specialist Haley Sickles poses next to a 2018 Dodge Demon vehicle during Press Days of the North American International Auto Show at Cobo Center in Detroit, Michigan, U.S., January 16, 2018. REUTERS/Rebecca Cook

A ruined ship with Communist Party symbol hammer and sickle lies on a salinated part of the Aral Sea coast line near the village of Akespe, south-western Kazakhstan, April 16, 2017. REUTERS/Shamil Zhumatov SEARCH "REVOLUTION RUSSIA" FOR THIS STORY. SEARCH "WIDER IMAGE" FOR ALL STORIES.

Sickles lie on top of freshly cut rice plants as farmers harvest them on a field at Khokana in Lalitpur, Nepal October 30, 2017. REUTERS/Navesh Chitrakar

An artisan places an artificial sickle on an idol of Hindu goddess Kali inside a pandal, or a temporary platform, on the occasion of Kali Puja festival in Kolkata, India, October 19, 2017. REUTERS/Rupak De Chowdhuri TPX IMAGES OF THE DAY

An artisan places an artificial sickle on an idol of Hindu goddess Kali inside a pandal, or a temporary platform, on the occasion of Kali Puja festival in Kolkata, India, October 19, 2017. REUTERS/Rupak De Chowdhuri

Henry and Christopher Flanagan-Kane and Shannon Sickles and Grainne Close speak to the media outside the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Michael Cooper

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Michael Cooper

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Michael Cooper

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Michael Cooper

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Michael Cooper

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

Henry and Christopher Flanagan-Kane with Shannon Sickles and Grainne Close depart the High Court in Belfast, Northern Ireland August 17, 2017. REUTERS/Clodagh Kilcoyne

A man stands near an element of interior design with a sickle and a hammer at Paveletskaya metro station in Moscow, Russia, May 29, 2017. REUTERS REUTERS/Grigory Dukor

Palestinian man Louy Al-Najar holds a sickle in his mouth as he arrives on a motorcycle to harvest wheat at a field in an area adjacent to the border with Israel, in Khan Younis in the southern Gaza Strip May 11, 2017. REUTERS/Ibraheem Abu Mustafa

A protester is silhouetted behind a Communist sickle and hammer banner as members and supporters of an underground Communist movement march along a street in Manila, Philippines March 31, 2017. REUTERS/Erik De Castro

The leader of the hardline Islamic Defenders Front (FPI), Habib Rizieq, speaks to journalists at police headquarters following his questioning by police over his claims that new bank notes contain symbols resembling the Communist hammer and sickle, which are illegal, in Jakarta, Indonesia January 23, 2017. REUTERS/Darren Whiteside

Vehicles drive past a monument covered with snow and forming a sickle and a hammer, which were displayed on the coat of arms of the Soviet Union, in the town of Pereslavl-Zalessky in Yaroslavl region, Russia, November 14, 2016. REUTERS/Maxim Shemetov

Vehicles drive past a monument covered with snow and forming a sickle and a hammer, which were displayed on the coat of arms of the Soviet Union, in the town of Pereslavl-Zalessky in Yaroslavl region, Russia, November 14, 2016. REUTERS/Maxim Shemetov