Some of London's telephone operators and engineers, trying out their gas masks at the anti-gas civilian training centre in Gloucester, where they were taught how to deal with gas attacks. (Photo by Harry Todd/Fox Photos/Getty Images). 13th February 1937

A dog from the K9 Division of the Sri Lanka Army’s Commando Regiment performs during an event to mark International Children’s Day at a school in Welisara, Colombo, Sri Lanka, 01 October 2016. Sri Lanka marks the Children's Day on 01 October with more emphasis on prevention of child abuse. (Photo by M.A. Pushpa Kumara/EPA)

In this February 26, 1962 file photo, Mercury astronaut John Glenn, and his wife, Annie, ride in the back of an open car with Vice-President Johnson during a parade in Glenn's honor in Washington. The Capitol is seen in the background. Glenn, the first American to orbit Earth who later spent 24 years representing Ohio in the Senate, died Thursday, Dec. 8, 2016, at the age of 95. (Photo by AP Photo)

Spectators dressed as leprechauns attend St Patrick's Day parade in Dublin on March 17, 2014. (Photo by Peter Muhly/AFP Photo)

French artist Gino rides the “Celestial Cyclo” tricycle built by him in Le Marais neighbourhood in Paris, France, August 15, 2015. (Photo by Pascal Rossignol/Reuters)

Attendees look at Volkswagen's BUDD-e, a long distance electric vehicle, displayed during a press event at CES 2016 at The Chelsea at The Cosmopolitan of Las Vegas on January 5, 2016 in Las Vegas, Nevada. CES, the world's largest annual consumer technology trade show, runs from January 6-9 and is expected to feature 3,600 exhibitors showing off their latest products and services to more than 150,000 attendees. (Photo by David Becker/Getty Images)

A woman watches the St. Patrick's day parade in Dublin, Ireland on March 17, 2017. St. Patrick's Day is marked annually on 17 March to commemorate Saint Patrick, a patron saint of Ireland. (Photo by Clodagh Kilcoyne/Reuters)

A zookeeper wearing orangutan costume tries to escape while zookeepers hold up a net in an attempt to capture it during an Escaped Animal Drill at Tama Zoological Park in Tokyo, Japan on February 22, 2019. The annual escape drill is held to train zookeepers what to do in the event of an animal escape. This year a member of staff wearing an orangutan costume was captured and subdued with large nets, sticks and tranquilizer guns to make sure the orangutan did not get away. (Photo by Rodrigo Reyes Marin/ZUMA Wire/Alamy Live News)