"SyntaxError: invalid syntax" running code in Doing Math With Python b

[saucerdesigner]

Hello, I'm scratching my head trying to get the code in the book Doing Math With Python by Amit Saha on page 9 to work.

Python 3.8.5 (default, Jul 28 2020, 12:59:40)
[GCC 9.3.0] on linux
Type "help", "copyright", "credits" or "license()" for more information.

>>> from fractions import Fraction
>>> try:
    a = float(input('Enter a number: '))
    #keyword except doesn't un-indent, I have to force it with a backspace
except ValueError:
    print('You entered an invalid number')
    Enter a number 3/4
    
SyntaxError: invalid syntax
>>>

What am I doing wrong? Wrong python version?

Regards,

David