How do I reverse each word in a string, but in the same sentence order?

How do I reverse each word in a string, but in the same sentence order?

I tried doing this
while 1:
line = input('Line: ')
print(line[::-1])
but all that did was reverse the whole sentence, I was wondering if
someone could help me with a program that converts 'hello world' to 'olleh
dlrow' instead of 'dlrow olleh', and how do I make a loop that stops when
the input is nothing, or just a space? Thank you in advanced!