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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def can_arrange(arr):
    """Create a function which returns the largest index of an element which is not greater than or equal to the element immediately preceding it. If no such element exists then return -1. The given array will not contain duplicate values. can_arrange([1,2,4,3,5]) = 3 can_arrange([1,2,3]) = -1 """
    ind=-1
    i=1
    while i<len(arr):
      if arr[i]<arr[i-1]:
        ind=i
      i+=1
    return ind
