The decorator pattern can be used to extend (decorate) the functionality of a certain object statically, or in some cases at run-time, independently of other instances of the same class, provided some groundwork is done at design time. This is achieved by designing a new Decorator class that wraps the original class. This wrapping could be achieved by the following sequence of steps:
Painters and paperhangers stand for prolonged periods. Their jobs also require a considerable amount of climbing, bending, kneeling, crouching, crawling and reaching with arms raised overhead often on scaffolding, ladders, and working at heights. Painters often work outdoors but seldom in wet, cold or inclement weather. Painters wear masks to reduce exposure to hazardous materials or paint fumes when working in areas with poor ventilation. Much of the work is done alone requiring independent thinking, safety awareness and ability to communicate with the customer. Special equipment is often used; such as equipment for welding, for use while scaffolding, on booms and lifts.
The decorator pattern is a design pattern that allows you to wrap an object such that it will appear to execute a given behavior in many different ways at different points in program execution. This is especially useful when you want an object to have different behaviors at but are unable to mutate the object. The decorator pattern is a useful way to implement dynamic behavior without needing an extended inheritance-based class hierarchy. To use the decorator pattern you need four elements: a component interface; a concrete component; a decorator abstraction; and, a concrete decorator. The interface sets the contract for both component and decorator behavior, the decorator abstraction contains a pointer to some concrete component, and the concrete decorators wrap a concrete component and override behavior if desired.
John Mansell Smith has been a self-employed painter & decorator for four years. He explains what it’s like to run your own business. “I became a self-employed painter & decorator when I took early retirement from my professional job in London, where I was employed as a Principal Building Surveyor. When I retired, I needed some additional income to supplement my pension, and having been in the building industry I was fully aware of the standard and quality which would be required to produce work to a professional standard. For a typical day at work, I usually arrive at the job at 8.30 am, and then depending on the sort of work I am doing it will vary a great deal. I could be undertaking external decorations or internal decorations, but in each case it would require covering and protecting the client's furniture, preparation of surfaces, washing down the walls, painting, wallpapering, cleaning up, etc. I try to leave at about 4.30 pm, but this may vary depending on the stage that I have reached with the job. In terms of likes and dislikes, I don’t enjoy working outside in poor weather, although I try to plan my workload to avoid this. However, I do like the freedom of being my own boss and getting complimented on a good job. If you wanted to be a painter and decorator, you would have to decide whether you wish to work for a company with the benefits such as holiday pay, but with the constraints of not being your own boss, or working for yourself with the freedom this gives but also the uncertainty of workload. As a self-employed person I can charge about £15 per hour for work that I do on an hourly rate, or I base any calculations on this rate when I am producing an estimate for a client. In attempting to find work, I would try the job centre, trade journals, large decorating companies, the internet and building training boards. To do the job you need to be a clean, neat worker with an eye for detail. The job you produce is the final result that the client will see, so it is vital that you can produce a finished job that you would be happy to have in your own home.

In Python 2.4a3 (to be released this Thursday), everything remains as currently in CVS. For 2.4b1, I will consider a change of @ to some other single character, even though I think that @ has the advantage of being the same character used by a similar feature in Java. It's been argued that it's not quite the same, since @ in Java is used for attributes that don't change semantics. But Python's dynamic nature makes that its syntactic elements never mean quite the same thing as similar constructs in other languages, and there is definitely significant overlap. Regarding the impact on 3rd party tools: IPython's author doesn't think there's going to be much impact; Leo's author has said that Leo will survive (although it will cause him and his users some transitional pain). I actually expect that picking a character that's already used elsewhere in Python's syntax might be harder for external tools to adapt to, since parsing will have to be more subtle in that case. But I'm frankly undecided, so there's some wiggle room here. I don't want to consider further syntactic alternatives at this point: the buck has to stop at some point, everyone has had their say, and the show must go on.


Component Interface: The component interface is an abstraction describing the behaviors of the components that you will eventually use in your program. Any objects that will use these components will do so through the interface, meaning that they are principally concerned with the abstraction (not the actual object). This is what allows both objects and wrapped objects to be considered to be the same type.
The primary objection to this form is that it requires "peeking inside" the method body to determine the decorators. In addition, even though the code is inside the method body, it is not executed when the method is run. Guido felt that docstrings were not a good counter-example, and that it was quite possible that a 'docstring' decorator could help move the docstring to outside the function body.
Action painting, sometimes called gestural abstraction, is a style of painting in which paint is spontaneously dribbled, splashed or smeared onto the canvas, rather than being carefully applied.[32] The resulting work often emphasizes the physical act of painting itself as an essential aspect of the finished work or concern of its artist. The style was widespread from the 1940s until the early 1960s, and is closely associated with abstract expressionism (some critics have used the terms "action painting" and "abstract expressionism" interchangeably).
... the keyword starting the line that heads a block draws a lot of attention to it. This is true for "if", "while", "for", "try", "def" and "class". But the "using" keyword (or any other keyword in its place) doesn't deserve that attention; the emphasis should be on the decorator or decorators inside the suite, since those are the important modifiers to the function definition that follows. ...
I am a fully qualified painter and decorator and pride myself on offering a hassle free and affordable service where the customer’s needs always take priority, as do excellent quality workmanship and operating to modern standards. We are confident that we can meet all your requirements on your next painting and decorating project and also exceed your expectations when it comes to quality and affordable painters and decorators in Crook.
Dougie is a Peebles based Painter and Decorator.  He prides himself on reliability, dedication and to providing customers with a comprehensive range of services with best quality preparation and finishes.  Dougie has over 30 years decorating experience covering  Peebles and surrounding areas and would be delighted to advise and assist with all your decoration needs.
Using functions with "action-at-a-distance" through sys.settraceback may be okay for an obscure feature that can't be had any other way yet doesn't merit changes to the language, but that's not the situation for decorators. The widely held view here is that decorators need to be added as a syntactic feature to avoid the problems with the postfix notation used in 2.2 and 2.3. Decorators are slated to be an important new language feature and their design needs to be forward-looking, not constrained by what can be implemented in 2.3.
Using functions with "action-at-a-distance" through sys.settraceback may be okay for an obscure feature that can't be had any other way yet doesn't merit changes to the language, but that's not the situation for decorators. The widely held view here is that decorators need to be added as a syntactic feature to avoid the problems with the postfix notation used in 2.2 and 2.3. Decorators are slated to be an important new language feature and their design needs to be forward-looking, not constrained by what can be implemented in 2.3.
I am a fully qualified painter and decorator and pride myself on offering a hassle free and affordable service where the customer’s needs always take priority, as do excellent quality workmanship and operating to modern standards. We are confident that we can meet all your requirements on your next painting and decorating project and also exceed your expectations when it comes to quality and affordable painters and decorators in Crook.
In general, functions in Python may also have side effects rather than just turning an input into an output. The print() function is a basic example of this: it returns None while having the side effect of outputting something to the console. However, to understand decorators, it is enough to think about functions as something that turns given arguments into a value.
Component Interface: The component interface is an abstraction describing the behaviors of the components that you will eventually use in your program. Any objects that will use these components will do so through the interface, meaning that they are principally concerned with the abstraction (not the actual object). This is what allows both objects and wrapped objects to be considered to be the same type.

The invention of photography had a major impact on painting. In the decades after the first photograph was produced in 1829, photographic processes improved and became more widely practiced, depriving painting of much of its historic purpose to provide an accurate record of the observable world. A series of art movements in the late 19th and early 20th centuries—notably Impressionism, Post-Impressionism, Fauvism, Expressionism, Cubism, and Dadaism—challenged the Renaissance view of the world. Eastern and African painting, however, continued a long history of stylization and did not undergo an equivalent transformation at the same time.[citation needed]
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