With Python3 refactoring code

Now Python 3 is the mainstream.

Author: ttzc

ex20.py

@@ -4,8 +4,7 @@
 
 
 def print_all(f):
-    print
-    f.read()
+    print(f.read())
 
 
 # seek(n) to read a file's content from byte-n
@@ -14,22 +13,18 @@ def rewind(f):
 
 
 def print_a_line(line_count, f):
-    print
-    line_count, f.readline()
+    print(line_count, f.readline())
 
 
 current_file = open(input_file)
 
-print
-"First let's print the whole file:\n"
+print("First let's print the whole file:\n")
 print_all(current_file)
 
-print
-"Now let's rewind, kind of like a tape."
+print("Now let's rewind, kind of like a tape.")
 rewind(current_file)
 
-print
-"Let's print three lines:"
+print("Let's print three lines:")
 current_line = 1
 print_a_line(current_line, current_file)