Program to find mirror characters in a string

def mirrorChars(input,k):

original = 'abcdefghijklmnopqrstuvwxyz'

reverse = 'zyxwvutsrqponmlkjihgfedcba'

dictChars = dict(zip(original,reverse))

prefix = input[0:k-1]

suffix = input[k-1:]

mirror = ''

for i in range(0,len(suffix)):

mirror = mirror + dictChars[suffix[i]]

print (prefix+mirror)

if __name__ == "__main__":

input = 'paradox'

k = 3

mirrorChars(input,k)