replace the whole 'not'...'poor' substring with 'good'.py

# Write a Python program to find the first appearance of the substring'not' and 'poor' from a given string, if 'not' follows the 'poor', replace thewhole 'not'...'poor' substring with 'good'. Return the resulting string.

a=input('enter a words: ')
k=a.replace('not poor','good')
print(k)