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>>> x,y,f=5,5,'Free';xx,yy,p=x/2-1 if not x%2 else x//2,y/2-1 if not y%2 else y//2,max(len(str(x*y)),len(f));nums=list(range(1,75));__import__('secrets').SystemRandom().shuffle(nums);print('\n'.join([' '.join([f if r==xx and i==yy else f'{nums[r*y+i]:>{p}}' for i in range(x)])for r in range(y)]))
73 67 44 68 51
69 37 31 22 26
55 12 Free 10 30
28 25 38 50 19
45 57 48 21 18