string replace 字串 單字 更改

s = 'A penny saved is a penny earned.'

print (s)

print(s.replace('n','l'))

print(s)

print(s.replace('penny','dollar'))

print(s.replace('penny','dollar',1))

輸出：

A penny saved is a penny earned.

A pelly saved is a pelly earled.

A penny saved is a penny earned.

A dollar saved is a dollar earned.

A dollar saved is a penny earned.