Concrete Decorator: Here we have two concrete decorators, ExcitedMessageDecorator and QuizzicalMessageDecorator, each of which descends from the abstract MessageDecorator class. However, these decorators do have special behavior in that they override the GetMessage and PrintMessage behaviors and enhance them by calling the base version from MessageDecorator (which in turn delegates to the relevant IMessage object) and then appending exclamations.
In object-oriented programming, the decorator pattern is a design pattern that allows behavior to be added to an individual object, dynamically, without affecting the behavior of other objects from the same class.[1] The decorator pattern is often useful for adhering to the Single Responsibility Principle, as it allows functionality to be divided between classes with unique areas of concern.[2] The decorator pattern is structurally nearly identical to the chain of responsibility pattern, the difference being that in a chain of responsibility, exactly one of the classes handles the request, while for the decorator, all classes handle the request.

The term outsider art was coined by art critic Roger Cardinal in 1972 as an English synonym for art brut (French: [aʁ bʁyt], "raw art" or "rough art"), a label created by French artist Jean Dubuffet to describe art created outside the boundaries of official culture; Dubuffet focused particularly on art by insane-asylum inmates.[33] Outsider art has emerged as a successful art marketing category (an annual Outsider Art Fair has taken place in New York since 1992). The term is sometimes misapplied as a catch-all marketing label for art created by people outside the mainstream "art world," regardless of their circumstances or the content of their work.


We are looking for a Maintenance Operative for a brand new residential development in Southall. Full of gardens, parks, trees and water; this contemporary development is a vibrant place to work with a brilliant team of people. As Maintenance Operative you will ensure the site is well maintained providing a clean and secure environment for residents and guests at all times. Supporting the Development Manager you will keep Health & Safety standards to a maximum. Must have a full clean driving license (to operate the estate vehicle) and Construction Skills Certification Scheme (CSCS) card. Our client is one of the UK's leading residential property management companies. They are a professional and creative employer who really put their people's best interests first. Always looking for the best ideas and solutions to look after people, their homes and communities; you'll be a valued member of this lovely company. Key responsibilities: Provide general maintenance support to the Development Liaise with and provide access to authorised contractors and tradesmen Report defects / incidents (either observed or reported) and take the corrective action Carry out monthly emergency light system checks and ensure monthly fire alarm checks are undertaken with Development Manager Maintain accurate records of maintenance / lighting issues Undertake any routine general repairs /

This code works for our purposes but it’s not exactly dynamic. If we wanted our initial simpleMsg object to sometimes act excited and sometimes quizzical, we could only do so by instantiating entirely new objects from the relevant subclass. Moreover, the ExcitedAndQuizzicalMessage is really just a combination of ExcitedMessage and QuizzicalMessage and probably shouldn’t have its own class. To fix these problems, let’s now return to the decorator pattern and see how it might help us.
After 2.4a2 was released, in response to community reaction, Guido stated that he'd re-examine a community proposal, if the community could come up with a community consensus, a decent proposal, and an implementation. After an amazing number of posts, collecting a vast number of alternatives in the Python wiki [18], a community consensus emerged (below). Guido subsequently rejected [22] this alternate form, but added:
NOTE  A Property Descriptor is not provided as an argument to a property decorator due to how property decorators are initialized in TypeScript. This is because there is currently no mechanism to describe an instance property when defining members of a prototype, and no way to observe or modify the initializer for a property. The return value is ignored too. As such, a property decorator can only be used to observe that a property of a specific name has been declared for a class.
When we instantiate a SimpleMessage and then pass it to the various decorators, we now get new behavior. Moreover, since both the concrete component and the concrete decorators all implement / descend from IMessage, they are interchangeable as far as the program is concerned, meaning that we can loop over them together. Further, rather than having to create a new ExcitedAndQuizzicalMessageDecorator class, we were able to achieve the same effect by double wrapping a SimpleMessage object (first in an ExcitedMessageDecorator and then in a QuizzicalMessageDecorator). Finally, note that despite having been passed into various decorators, our simpleMsg object remains unchanged at the end of the program.
Did you get it? We just applied the previously learned principles. This is exactly what the decorators do in Python! They wrap a function and modify its behaviour in one way or the another. Now you might be wondering that we did not use the @ anywhere in our code? That is just a short way of making up a decorated function. Here is how we could have run the previous code sample using @.

The oldest known paintings are at the Grotte Chauvet in France, which some historians believe are about 32,000 years old. They are engraved and painted using red ochre and black pigment, and they show horses, rhinoceros, lions, buffalo, mammoth, abstract designs and what are possibly partial human figures. However, the earliest evidence of the act of painting has been discovered in two rock-shelters in Arnhem Land, in northern Australia. In the lowest layer of material at these sites, there are used pieces of ochre estimated to be 60,000 years old. Archaeologists have also found a fragment of rock painting preserved in a limestone rock-shelter in the Kimberley region of North-Western Australia, that is dated 40,000 years old.[7] There are examples of cave paintings all over the world—in Italy, France, Spain, Portugal, China, Australia, Mexico,[8] etc. In Western cultures, oil painting and watercolor painting have rich and complex traditions in style and subject matter. In the East, ink and color ink historically predominated the choice of media, with equally rich and complex traditions.
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