print v. print()

[Frederick Williams]

I am learning Python from Hammond & Robinson's _Python Programming on
Win32_, January 2000 edition.  This

   print "Sleeping for 10 seconds"

which appears in some example code, fails to... um... Compile? 
Interpret?  Well, whatever the word is, it fails.  Trial and error
revealed that

   print("Sleeping for 10 seconds")

does the trick.  I am using version 3.1.2, presumably the book's authors
used some earlier version.  

So why the change from print to print()?

I should warn you that I know nothing about computers in general or
Python in particular.

-- 
I can't go on, I'll go on.