human
Find the largest number that can be formed by changing at most K digits | Function to return the maximum number that can be formed by changing at most k digits in str.
For every digit of the number.
If no more digits can be replaced.
If current digit is not already 9.
Replace it with 9.
One digit has been used.
Driver code"
How can the above be solved in Python?

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Give me a code to find the largest number that can be formed by changing at most K digits and the other steps required?
assistant
#Here is code to find the largest number that can be formed by changing at most K digits and the other steps required.
 def findMaximumNum ( st , n , k ) :
	for i in range ( n ) :
		if ( k < 1 ) :
			break
		if ( st [ i ] != '9' ) :
			st = st [ 0 : i ] + '9' + st [ i + 1 : ]
			k -= 1
	return st
st = "569431"
n = len ( st )
k = 3
print ( findMaximumNum ( st , n , k ) )