import re

def wrapper_huepper(new_str, n):
	counter = 0
	n = n
	new_str = new_str
	def replace(matchobj):
		nonlocal counter
		counter = counter + 1
		if counter == n:
			return new_str
		return matchobj.group(0)
	return replace

test_str = 'aBaBaBaBaB'
w1 = '********'
replace = wrapper_huepper(w1, 3)
x = re.sub(r"(?<=\w)[A-Z]", replace, test_str)
print(x)