1*ac2a7c1bSSadaf Ebrahimi{ 2*ac2a7c1bSSadaf Ebrahimi? explicit key1 : explicit value, 3*ac2a7c1bSSadaf Ebrahimi? explicit key2 : , # Explicit empty 4*ac2a7c1bSSadaf Ebrahimi? explicit key3, # Empty value 5*ac2a7c1bSSadaf Ebrahimisimple key1 : explicit value, 6*ac2a7c1bSSadaf Ebrahimisimple key2 : , # Explicit empty 7*ac2a7c1bSSadaf Ebrahimisimple key3, # Empty value 8*ac2a7c1bSSadaf Ebrahimi} 9