Syntactic constraints. Python is a syntactically simple language with fairly strong constraints on what can and can't be done without "messing things up" (both visually and with regards to the language parser). There's no obvious way to structure this information so that people new to the concept will think, "Oh yeah, I know what you're doing." The best that seems possible is to keep new users from creating a wildly incorrect mental model of what the syntax means.
Surrealism is a cultural movement that began in the early 1920s, and is best known for the visual artworks and writings of the group members. Surrealist artworks feature the element of surprise, unexpected juxtapositions and non sequitur; however, many Surrealist artists and writers regard their work as an expression of the philosophical movement first and foremost, with the works being an artifact. Leader André Breton was explicit in his assertion that Surrealism was above all a revolutionary movement.
Abstract painting uses a visual language of form, colour and line to create a composition that may exist with a degree of independence from visual references in the world.[29][30] Abstract expressionism was an American post-World War II art movement that combined the emotional intensity and self-denial of the German Expressionists with the anti-figurative aesthetic of the European abstract schools—such as Futurism, Bauhaus and Cubism, and the image of being rebellious, anarchic, highly idiosyncratic and, some feel, nihilistic.[31]

Note that greet_bob(say_hello) refers to two functions, but in different ways: greet_bob() and say_hello. The say_hello function is named without parentheses. This means that only a reference to the function is passed. The function is not executed. The greet_bob() function, on the other hand, is written with parentheses, so it will be called as usual.

Painting is an important form in the visual arts, bringing in elements such as drawing, gesture (as in gestural painting), composition, narration (as in narrative art), or abstraction (as in abstract art).[2] Paintings can be naturalistic and representational (as in a still life or landscape painting), photographic, abstract, narrative, symbolistic (as in Symbolist art), emotive (as in Expressionism), or political in nature (as in Artivism).