new_contents: def iterative_binary_search(array, item):
  
      low = 0
      high = len(array) - 1
  
      while(low<=high):
  
          mid = (low+high)//2
  
          if (item == array[mid]):
              return mid
          elif item < array[mid]:
              high = mid - 1
          elif item > array[mid]:
              low = mid + 1
  
      return -1
  
  print ( iterative_binary_search([1,4,5,7], 5)) #2
  print ( iterative_binary_search([1,4,5,7], 10)) #-1
  
subject: Add iterative binary search algorithm implementation