[Tutor] Increase performance of the script

[Steven D'Aprano]

On Tue, Dec 11, 2018 at 09:07:58PM +0530, Asad wrote:
> Hi All,
> 
>           I used your solution , however found a strange issue with deque :

No you haven't. You found a *syntax error*, as the exception says:

> >>> print 'Deque:', d
>   File "<stdin>", line 1
>     print 'Deque:', d
>                  ^
> SyntaxError: invalid syntax

which means the error occurs before the interpreter runs the code. You 
could replace the above line with any similar line:

print 'Not a deque', 1.2345

and you will get the same error.

When you are faced with an error in the interactive interpreter, you 
should try different things to see how they effect the problem. Does the 
problem go away if you use a float instead of a deque? If you change the 
string, does the problem go away? If you swap the order, does the 
problem go away? What if you use a single value instead of two?

This is called "debugging", and as a programmer, you need to learn how 
to do this.


[...]
> In python 2.6 print statement work as print "Solution"
> however after import collection I have to use print with print("Solution")
> is this a known issue ?

As Peter says, you must have run 

from __future__ import print_function

to see this behaviour. This has nothing to do with import collection. 
You can debug that for yourself by exiting the interactive interpreter, 
starting it up again, and trying to print before and after importing 
collection.



-- 
Steve