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For 2023 - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.

Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!

I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Local and global variables
Functions, Modules and Packages example from a Well House Consultants training course
More on Functions, Modules and Packages [link]

This example is described in the following article(s):
   • Sample code with errors in it on our web site - [link]

This example references the following resources:

Source code: locvar.py Module: Y105
#!/usr/bin/env python

# Variable scope

first = 1

def one():
        "Double a global variable, return it + 3."
        global first
        first *= 2
        result = first+3
        return result

print("first now has the value",first)
print("result has the value",result)

""" ----------------------------------------------------------

** Important Note **

This is an example from our training material and illustrates
variable scope in Python. The variable called result within the
one function is local to that function, so is not visible outside
and so the program generates an error when run, as follows:

WomanWithCat:y105 grahamellis$ python3 locvar.py
Double a global variable, return it + 3.
first now has the value 8
Traceback (most recent call last):
  File "locvar.py", line 21, in <module>
    print("result has the value",result)
NameError: name 'result' is not defined
WomanWithCat:y105 grahamellis$

The subject of varaible scope and why "default local" is a good
idea is full covered in the training notes from which the code
above is copied ... see http://www.wellho.net/course/ypfull.html """

Learn about this subject
This module and example are covered on the following public courses:
 * Learning to program in Python
 * Python Programming
Also available on on site courses for larger groups

Books covering this topic
Yes. We have over 700 books in our library. Books covering Python are listed here and when you've selected a relevant book we'll link you on to Amazon to order.

Other Examples
This example comes from our "Functions, Modules and Packages" training module. You'll find a description of the topic and some other closely related examples on the "Functions, Modules and Packages" module index page.

Full description of the source code
You can learn more about this example on the training courses listed on this page, on which you'll be given a full set of training notes.

Many other training modules are available for download (for limited use) from our download centre under an Open Training Notes License.

Other resources
• Our Solutions centre provides a number of longer technical articles.
• Our Opentalk forum archive provides a question and answer centre.
The Horse's mouth provides a daily tip or thought.
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• All of these resources can be searched through through our search engine
• And there's a global index here.

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This web site is written and maintained by Well House Consultants.

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This is a sample program, class demonstration or answer from a training course. It's main purpose is to provide an after-course service to customers who have attended our public private or on site courses, but the examples are made generally available under conditions described below.

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