Structures of 7‐bromo‐1,3‐dihydro‐5‐(2‐pyridyl)‐2H‐1,4‐benzodiazepin‐2‐one (bromazepam, C14H10BrN3O) and 5‐(2‐fluorophenyl)‐1,3‐dihydro‐1‐methyl‐7‐nitro‐2H‐1,4‐benzodiazepin‐2‐one (flunitrazepam, C16H12FN3O3)