如何定义以小写形式返回我的字符串的 function？

Question

I am trying to define a function that makes a string of text inputed into lowercase.

def lowercase(text:str):
     text.lower()
     return text

Once I put my test sentence into this function, it still prints out uppercase letters.

Answer 1

.lower() returns a new value, therefor you need to store it in a variable or directly return this.

def lowercase(text:str):
     text = text.lower()
     return text

or

def lowercase(text:str):
     return text.lower()

Answer 2

def lowercase(text:str):
     return text.lower()

This should do it.

Answer 3

Try this:

def lower(text):
    lowered = text.lower()
    return lowered

You were returning text which was the input of the function, so the function returned the text which it received as input.