Astronaut Anne McClain takes part in egress training for the Crew Dragon at SpaceX’s Hawthorne,California, headquarters recently as part of a larger team of astronauts and engineers evaluating processes for the original generation of American spacecraft in development to carry astronauts to the International Space Station. Working inside a mock-up built by SpaceX to simulate the actual spacecraft, or the team practices leaving the spacecraft through the top hatch of the Crew Dragon as well as using the side hatch. The work is common in assessing spacecraft design. For astronauts,such rehearsals are regular exercise in mission preparations even in spacecraft that acquire been flying regularly.
Source: nasa.gov