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+.. Objectives
+.. ----------
+
+.. Prerequisites
+.. -------------
+     
+.. Author              : Nishanth Amuluru
+   Internal Reviewer   : 
+   External Reviewer   :
+   Checklist OK?       : <put date stamp here, if OK> [2010-10-05]
+
+Script
+------
+
+Hello friends and welcome to the tutorial on "Writing Python scripts"
+
+{{{ Show the slide containing title }}}
+
+{{{ Show the slide containing the outline slide }}}
+
+In this tutorial, we shall learn
+
+ * How write Python scripts 
+
+Often we will have to reuse the code that we haave written. We do that by
+writing functions. Functions are bundled into packages and are imported as and
+required in the script.
+
+Let us first write a function that computes the gcd of two numbers and save it
+in a script.
+
+{{{ Open an editor and start typing out the following code }}}
+::
+
+    def gcd(a, b):
+
+        while b:
+            a, b = b, a%b
+
+        return a
+
+We shall write an test function in the script that tests the gcd function every
+time the script is run.
+
+{{{ Add to the script }}}
+
+::
+
+    if gcd(40, 12) == 4:
+        print "Everything OK"
+    else:
+        print "The GCD function is wrong"
+
+Let us save the file as script.py in /home/fossee/gcd_script.py
+
+We shall run the script by doing
+::
+
+    $ python /home/fossee/gcd_script.py
+
+We can see that the script is executed and everything is fine.
+
+What if we want to use the gcd function in some of our later scripts. This
+is also possible since every python file can be used as a module.
+
+But first, we shall understand what happens when you import a module.
+
+Open IPython and type
+::
+
+    import sys
+    sys.path
+
+This is a list of locations where python searches for a module when it
+encounters an import statement.
+
+hence when we just did =import sys=, python searches for a file named sys.py or
+a folder named sys in all these locations one by one, until it finds one.
+
+We can place our script in any one of these locations and can import it.
+
+The first item in the list is an empty string which means the current working
+directory is also searched. 
+
+Alternatively, we can also import the module if we are working in same 
+directory where the script exists.
+
+Since we are in /home/fossee, we can simply do
+::
+
+    import gcd_script
+    
+We can see that the gcd_script is imported. But the test code that we added at
+the end of the file is also executed.
+
+But we want the test code to be executed only when the file is run as a python 
+script and not when it is imported.
+
+This is possible by using =__name__= variable.
+
+First we shall look at how to use the idiom and then understand how it works.
+
+Go to the file and add
+::
+
+    if __name__ == "__main__":
+        
+before the test code and indent the test code.
+
+Let us first run the code.
+::
+
+    $ python gcd_script.py
+
+We can see that the test runs successfully.
+
+Now we shall import the file
+::
+    
+    import gcd_script
+
+We see that now the test code is not executed.
+
+The __name__ variable is local to every module and it is equal to __main__ only
+when the file is run as a script.
+
+hence all the code that goes after __name__ == "__main__" is executed only when
+the file is run as a python script.
+
+{{{ Show summary slide }}}
+
+This brings us to the end of the tutorial.
+we have learnt
+
+ * What happens when we import a module
+ * How to use a script as a module
+ * How to write test functions using the __name__ idiom 
+
+{{{ Show the "sponsored by FOSSEE" slide }}}
+
+#[Nishanth]: Will add this line after all of us fix on one.
+This tutorial was created as a part of FOSSEE project, NME ICT, MHRD India
+
+Hope you have enjoyed and found it useful.
+Thankyou
+