# Map function and Lambda expression in Python to replace characters # Function to replace a character c1 with c2 # and c2 with c1 in a string S   def replaceChars(input,c1,c2):       # create lambda to replace c1 with c2, c2      # with c1 and other will remain same      # expression will be like "lambda x:     # x if (x!=c1 and x!=c2) else c1 if (x==c2) else c2"     # and map it onto each character of string     newChars = map(lambda x: x if (x!=c1 and x!=c2) else \                c1 if (x==c2) else c2,input)       # now join each character without space     # to print resultant string     print (''.join(newChars))  # Driver programif __name__ == "__main__":    input = 'grrksfoegrrks'    c1 = 'e'    c2 = 'r'    replaceChars(input,c1,c2)