SUDOKU

Write a number from 1 to 9 into each empty square in the grid so that every number from 1 to 9 appears exactly once in each horizontal row, each vertical column, and each 3×3 block.
273      1    
6            78
5      1        
      1  2      
    7  6  4    
      8  7      
8      5      6
  6          24
  3        98  
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