Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01572 byguest on 24 September 2021 230 ABSTRACT LEONARDO, Vol. 52, No.3,pp.230–235, 2019 quantum measurement. the principlesofquantumsuperposition,entanglementand CLOUD. CLOUDexplorescomplexityinthepostdigitalbyreferencing ofaninteractiveinstallation, to discusstheconceptionandform The authordrawsonherresearchexperienceinquantumcomputing and ComplexityinArt Quantum Computing s ’ t s i t r a nentially when zooming into the fundamental constituentsfundamental the into zooming when nentially than biology or finance. However, complexity increases expo ing metaphorical connections. focus on investigating concepts from such systems and creat Heather Barnett, Keith Tyson and Jennifer Steinkamp [8–10] of classical complex systems in properties aboutwrote [7] Johnson [6]). piece the to depth the (as composition jazz or artwork an of complexity the computational or certain [5]) problems solving of difficulty instance, one may talk about computational complexity (the down—for to pin difficult notoriously is definition its such As finance. to biology from disciplines across occurs thus tion for articulating complexity and I use my postdigital - installa andbroaderbring new techniques intoingwill ourtoolbox concepts believe fromquantumI ownterms. their comput - oncomplexity with interact and experience understand, to periment with new forms and techniques that enable people practitioners,importantculturalis researchit to ex- and all climate change in his book aroundnarrativesexploresMarshall George and sation[2], films his throughratives AdamexploresCurtis complexity popularreductivein nar sus evil, tales propagated by the (social) media. For instance, ver good or artificial, versusnatural simple to reduced are narratives or concepts detailed intricately often, So times. our of issue critical most the is complexity Understanding with thisissue. See www.mitpressjournals.org/toc/leon/52/3 forsupplementalfilesassociated London, SW7 2EU, U.K. Email: [email protected]. Libby Heaney (artist, physicist, tutor), , Kensington Gore, It is easy to believe that systems cannot be morethatsystemscannot complexbelieve Itbe to easy is and [4] systems large of feature generic a is Complexity to unpack these issues throughout this paper. this throughoutissues these unpack to CLOUD i L B B A e l c i t r e H y [1] and [1] BitterLake a Don’t Even Think About It [3]. For y e n Emergence , and artists such as HyperNormali-

- - - - of complexity through creative practices. exploration the for tool potential a thereforeand municate com and think humans how to related thus is theory tum economics,cognition and computational linguistics. Quan- cal framework appear in nonphysical ofaspects psychology, croscopic domain. That is,parts ofthe quantum mathemati- appliedaway quantumfrombe can physics’ logic mi- usual theory called quantum interactions [14] argues that recent quantum a systems, macroscopic to applied usually not is ics tion to a biological cell, is classical. And while quantum phys systems mentioned above, from the notes in a jazz composi- relevant to our everyday experience, since the physics of the some challenges along way. the ticulating complexity. I argue in the affirmative, while noting art and design practices would provide new methods for ar through effects quantum referencing whether ask may we tangled) to perform computation upon them [13]. Therefore that most composite quantum systems are too complex (en- argued has Eisert further.complexity the increase particles many entangled states of and dimensions infinite [12], span superposition principle enables a single quantum particle to the instance, For systems. (nonquantum) classical of that Importantly,fromdifferentcomplex[11]. complexity is this inherentlyare quantumsystems and level, basic most its at of the universe. the universe describes cussing quantum physics imagery, “there is an inherent, inherent, an is “there imagery, physics quantum cussing dis - when it puts JamesElkins problem.As a is this believe not do However, I 1). Part appendix (supplementary lights high paradox cat Schrödinger’s the as macroscopic, artworks, in physical represented be cannot effects quantum genuine since however, practices, creative through effects mentarity and poststructuralist theory, notably Derrida [16]. comple Bohr’s between relationships/disparities explores Plotnitskyand[15],agentialrealityof theory herdevelop to 1960s. More recently, Barad Bohr’sused philosophy-physics the since meaning and systems telematic of context the in extensivelyit discussed new.has Ascottnot is systems plex In fact, using quantum physics as a metaphor for com for metaphor a as physics quantum using fact, In quantumisphysics whyquestion importantto is it First, There are some contradictions in referencing quantum quantum referencing in contradictions some are There doi:10.1162/LEON_a_01572 ©2019 ISAST ------Fig. 1. CLOUD, 2015. (© Libby Heaney)

Fig. 3. People moving around in the space in front of CLOUD and remotely altering the patterns displayed, 2015. (© Libby Heaney)

Fig. 2. Close-up of CLOUD showing graphite and white octahedrons, 2015. (© Libby Heaney)

Fig. 4. The pixels in CLOUD randomly positioning, 2015. (© Libby Heaney) ­systemic contradiction in this practice: it says both ‘quantum phenomena need to be visualized [in order to teach it]’ and Each pixel is half shaded with graphite, and the other half that ‘quantum phenomena aren’t amenable to visualization’ ” is left as blank paper (Fig. 2). Behind are the electronics— [17]. However, quantum physics images are useful as “free namely a servo motor for each pixel and ~500m of wiring. versions of a rigorous practice, intended to be suggestive The orientations of the pixels are determined, in part, by data and approximate rather than dependable and exact” [18] and from a Microsoft Kinect depth camera, which senses the area “even images regarded by members of the physics commu- in front of the piece, where a coded, invisible copy of the nity as patently inadequate or misguided can also come to physical structure is digitally “reflected” across the floor. seem potentially helpful” [19]. So while CLOUD focuses on The presence of people in this space causes CLOUD to experience as well as representation, it could also be viewed change its configuration. Before anyone enters the space, the as a sequence of images that renders quantum computing pixels are in an ordered, low-entropy configuration: Every both “unpicturable and picturable,” articulating complexity single one is facing the same way (half-colored and half- through traces of properties that are essentially inconceivable. blank). Then, as participants walk around in the space, their paths are gradually mapped onto CLOUD through a random CLOUD orientation of the corresponding pixels (Fig. 3). Each location CLOUD is an installation that spans the digital and the in front of CLOUD has a one-to-one link with a pixel such physical. The physical consists of 54 independently rotating that when a person steps into a location, the code control- octahedral “pixels” made from paper, tessellated within a ling the installation randomly chooses to rotate the linked hand-knotted linen net that in turn is suspended by a scaffold pixel left or right to reveal fully its shaded or blank side [S-2 frame (commissioned as part of a wider exhibition) (Fig. 1). - code] (Fig. 4). Overall, the installation thus evolves from an

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Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01572 by guest on 24 September 2021 Fig. 5. Two Necker cubes placed next to each other illustrate the correlations of entanglement.

ordered to a random state, contingent on how people move putation [23], where the utilization of entanglement and in the space, with the pixels slowly reordering themselves quantum measurement to drive computation can be seen after people have moved away from the piece for a certain most strikingly. amount of time. Measurement-based quantum computation proceeds The functioning ofCLOUD was inspired, in part, by three as follows. Before the computation takes place, a large en- features of science [20]. First, the su- tangled state, called a cluster state, is created between hun- perposition principle states that any quantum system can dreds of spatially localized qubits [24]. This forms a grid-like be in multiple states simultaneously—for instance, a single structure, in some sense like hundreds of Necker cubes ar- massive particle such as a carbon C-60 “buckyball” molecule ranged in a square. For massive particles, qubits are logically passing through two spatially separated spits [21]. When represented by electron spin. The entanglement between quantum mechanics is applied to computation, a bit becomes neighboring particles means that the information about the a quantum bit (or qubit) and is no longer in either a zero or orientations of individual spins is nonlocally distributed over one state but may be in both simultaneously. Superposition is the entire system [25]. Once a cluster state is engineered, the somewhat like, but fundamentally different from, the famous computation proceeds via a sequence of different measure- gestalt image of two faces or a vase—depending on where in ments that themselves encode the algorithm on the individ- the image the observer looks, they will see one or the other ual qubits in the cluster state. These measurements destroy representation. the spin-entanglement between the measured qubits and the The second feature that informed this installation is quan- rest of the lattice. The measured qubits are in random states, tum entanglement. This is the extension of quantum super- but the remaining parts of the cluster state—yet to be mea- position for two or more quantum particles. In entangled sured—draw closer to the final solution of the computation. states, the information about the properties of each particle Since measurement-based quantum computing was my (for instance their spin or position) is delocalized over all the starting point for CLOUD, it felt natural to explore complex- particles, and the entire system is in a superposition of vari- ity by promoting the viewer to the role of the measuring ous configurations [22]. Entanglement is illustrated, again in device/observer. In classical physics, a measurement does not a “suggestive and approximate” way, by placing two Necker irreversibly change the system’s state—the disturbance either cubes next to each other (Fig. 5). The viewer sees both cubes is negligible or can be determined and subtracted out. Using with either one perspective or the other. The orientations this distinction, artworks [26] that passively interact with the of the two cubes are correlated—one never sees them with observer (i.e. the viewer does not actively change the state opposite orientations provided they are next to each other. of the artwork) may be situated in the classical domain. On Furthermore they both exist in two states simultaneously. the other hand, artworks like CLOUD and Very Nervous Sys- The third property is quantum measurement. An act of tem by David Rokeby [27], for example, that respond to the measurement irreversibly and ontologically changes the state audience’s input, are quantum-like as they bring the viewer of a quantum system, which “decoheres” it into one classi- into the work as a participator, and the total system changes cally observable state probabilistically. Here there are loose irreversibly as a result of the agential intra-actions. metaphorical connections to second-order cybernetics and Bentham’s Panopticon model of a prison, which is explored Intra-activity and Entanglements in depth elsewhere (supplementary appendix Part 3). The notion of intra-action was introduced by Barad as a These three concepts come together in quantum comput- component of agential realism. Agential reality is a “posthu- ing, where certain algorithms process information more ef- manist performative approach to understanding technosci- ficiently than classical computers. There are many proposed entific and other naturalcultural practices that specifically architectures for quantum computing. The scheme that in- acknowledges and takes account of matter’s dynamism.” spired CLOUD is called measurement-based quantum com- Here posthumanist refers to taking issue with anthropocen-

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Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01572 by guest on 24 September 2021 tric viewpoints and a performative approach refers to direct material engagement with the world. Intra-actions (in con- trast to “interaction,” “which presumes the prior existence of independent entities or relata”) determine the boundary and properties of the components of phenomena and give meaning to concepts. Barad writes, “The universe is agential intra-activity in its becoming” [28]. Agential realism draws extensively on Bohr’s philosophy- physics and references quantum effects such as entanglement and quantum measurement. Entanglement and measure- ment were a starting point for CLOUD; so does CLOUD embody elements of Barad’s theory? I believe so. The “entan- glement” of CLOUD with the participators can be seen as a series of phenomena, which Barad directly links to quantum Fig. 7. The hand-knotted linen net that supports the rotating pixels contains physics via Bohr. “For Bohr, things do not have inherently indecipherable information embedded via a Morse code-like knotting macramé determinate boundaries or properties, and words do not scheme. The metaphor of the real and virtual seems apt to explore concepts have inherently determinate meanings” [29]. The phenom- from quantum physics in the macroscopic domain. The invisible sensing of the ena (of meaning and mattering) produced by CLOUD are in Kinect and the computer code running silently and perhaps unnoticed in the background can be seen as metaphors of “unpicturable” quantum processes continuous flux and do not have determinate boundaries or at work. Much like how quantum computing is driven through specific material properties—they are continuously coming into being. Barad processes encoding algorithms, audience members come to matter via writes that “matter is produced and productive, generated these partially invisible technologies (supplementary appendix Part 3). and generative” [30], which are the intra-active feedbacks be- (© Libby Heaney) tween the audience and CLOUD—patterns/configurations/ meanings are produced and are productive of further intra- information, and this cosmic computation is responsible actions. By necessarily taking quantum physics as a starting for the complexity of the universe, including us [32]. Lloyd’s point, CLOUD thus breaks down classical object-subject, computational universe is similar to Barad’s agential realism, natural-cultural boundaries, placing it and the articulated and both suggest the world is already playing the role of the complexity firmly within the postdigital. contemporary artist, making real the ever-changing results As a postdigital artwork, CLOUD brings together materials (matter and meaning) of a vast computation that has been that are close to “natural” (i.e. linen, paper, graphite) with under way for billions of years. Barad writes, “Agency is not digital technologies (Fig. 6), bringing to life “differential pat- an attribute but the ongoing reconfigurations of the world” terns of mattering” [31] between humans and nonhumans. [33]. These reconfigurations are Lloyd’s complex structures. While producing the linen net, I followed a self-devised Thus “predigital” and “postdigital” are equivalent. CLOUD Morse code macramé (knotting) pattern (left knot = dot, follows the spirit of this, revealing complexity in both the right knot = dash) to embed undecipherable information— real and virtual, in nature and culture. messages—into the net’s physical texture (Fig. 7). Physicist Relating art to aspects of quantum physics is not new, and Seth Lloyd has argued that the universe processes quantum it is important to revisit some of these early ideas now that quantum physics has been associated with computing. Ascott wrote about a field theory for art and related it to quantum physics:

[A field theory for art] is not a one-way linearity but the interrogation of probabilities by the viewer. . . . The viewer/ observer must be a participator and is of operational im- portance in the total behavior of the system. A field theory of art must pay attention to the participator [34].

The cluster state of measurement-based quantum compu- tation reminds me of this field of potentiality—the potential to be projected into the outcomes of computations. CLOUD responds to this and becomes a field of probabilities incor- porating the viewers. A field theory for art is intra-active art—a universe of mattering in the state of becoming. Simi- lar to Ascott’s field theory, Barad describes how apparatuses (“the conditions of possibility for determinate boundaries

Fig. 6. The visible tangle of wires behind the pixels expresses a natural and properties of objects and meanings of embodied con- form and contrasts with the rigid geometry of the octahedrons and scaffold. cepts within the phenomenon” [35]) “are specific material (© Libby Heaney) reconfigurations of the world that do not merely emerge in

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Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01572 by guest on 24 September 2021 time but iteratively reconfigure spacetimematter as part of CLOUD simultaneously become measuring apparatus and the ongoing dynamism of becoming” [36]. Ascott also ref- measured. Via a random number generator in the Processing erences the nonlinearity of time in postmodern art. Rather code, for the same number of people in the digitally sensed than encompassing linearity, CLOUD, through its reversible area in exactly the same locations, different resulting patterns movement over time, acts as a metaphor “in its reversibility will occur. This is a poetic version of the measurement pro- with the new physics” [37], thereby displaying a temporal cess in the quantum computation scheme, encouraging the complexity as well as complexity in its spatial structure. participators to create structures as they explore the space, For Barad, concepts become specific material arrange- (mis)understanding the algorithmic rules, thereby creating ments. CLOUD is abstracted to focus on how the interaction, further complex structures. These intra-actions give rise to form and materials articulate patterns of complexity without Barad’s phenomena where concepts are embodied in physi- the complication of explicit content. Thus the audience may cal apparatuses, and matter and meaning are entwined. As attribute different complex phenomena to CLOUD’s struc- Ascott wrote, up close to the work, “the viewer/observer must tures/patterns, which themselves become the content of the be a participator and is of operational importance in the total work—the specific material arrangements are the concepts. behavior of the system” [40]; they and the nonhuman ele- This may open up meanings rather than narrow them. There- ments are performing the computation, which like Lloyd’s fore CLOUD may be considered as meta-modern in that it computational universe never reaches a final solution. reengages modernist methods in order to address subject I believe the indeterminate nature of the interaction and matters outside the original interest of the modernists them- the invisibility of the code/sensed area in front of the work selves. encourages people to investigate and explore the complex- Taking the cluster state as inspiration, each octahedron ity on their own terms—for them to experience it—through pixel is spatially located and has an intrinsic property, like intra-activity. On the opening night of the show, I returned electron spin, in flux. Octahedrons are platonic solids. to the piece to find around 20 people in the sensed space However, in CLOUD the octahedron pixels’ perfect sym- jumping up and down synchronized with one another, in metry has been replaced by two distinct states—different what I can only assume was an attempt to generate more pieces of information—the rough graphite on one side con- interesting or perhaps more coherent—ordered—patterns. trasting the smooth white paper on the other. This is a discon- There were no didactic panels with details about the algo- tinuity in the pure platonic ideal reminiscent but essentially rithm, thus this was an entangling of collective thought and a discretized (qubit) version of wave-particle duality for our action. This many-body entanglement of humans and non- digital age. Octahedrons tessellate the space uniformly and humans, matter and meaning is an emergent phenomenon offer up to two distinct viewpoints for audience members that refutes individualism depending on their relative position to the left or right of At other times, while trying to understand the functioning the piece. of the piece, the participators would rush in from the side These different perspectives are a metaphor for entangle- of the work and stand very close to the pixels (some would ment, even for viewers outside the range of the Kinect. Barad also wave or dance). Here I assume that by recognizing the uses the word entanglement as “not simply to be intertwined Kinect sensor and by remembering their previous interac- with another, as in the joining of separate entities, but to tions with such equipment, these participators believed new lack an independent, self-contained existence” [38]. Thus patterns would be generated. In reality their presence close here information about the overall state of CLOUD and its to the piece just randomly rotated (Fig. 7) the lowest pix- meaning is delocalized across the viewers standing in the els—the rest of the piece remained ordered (provided no vicinity of the piece. A viewer on the left and a viewer on the one else was in the space). Some of these people would then right would need to come together to describe the work as stand further back and notice that pixels higher up the lattice a whole. For the individual viewers on the left or the right, would randomly flip, hence giving further information to the it is as if quantum measurements had taken place, due to algorithmic complexity. their mutually exclusive perspectives. While this idea of mul- tiple perspectives is ubiquitous throughout postmodernist Conclusion art (Bishop writes about it in relation to installation art, for While the number of different configurations of the pixels instance [39]), in its linkage to quantum entanglement, new in CLOUD cannot be infinite, the three orientations of each directions in expressing complexity through meaning and pixel (colored, white or half/half) lead to 354 = 5.46 × 1026 matter may open up with further experimentations (see different possible patterns. Coupled with the potential of supplementary appendix Part 4). the audience, CLOUD gives rise to an infinite field theory Now let us turn to the interaction of participators medi- of matter and meaning, forming a postdigital—intra-active ated by the Kinect. Different configurations of CLOUD and natural and artificial—computer, which, similarly to Lloyd’s the audience continuously come into being. These intra- universe, uses randomness and computation to generate actions generate further intra-actions. Participators and complexity.

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Downloaded from http://www.mitpressjournals.org/doi/pdf/10.1162/leon_a_01572 by guest on 24 September 2021 References and Notes 21 Markus Arndt et al., “Wave-Particle Duality of C-60 Molecules” Nature 401 (1999) pp. 680–682. Available at www.qudev.ethz.ch 1 Adam Curtis, Bitter Lake (2015): www.bbc.co.uk/programmes /phys4/studentspresentations/waveparticle/arndt_c60molecules /p02gyz6b (accessed 23 October 2016). .pdf (accessed 8 August 2016). 2 Adam Curtis, HyperNormalisation (2016): www.bbc.co.uk/pro 22 Maggie McKee, “Introduction: Quantum World,” New Scientist (4 grammes/p04b183c (accessed 24 October 2016). September 2006): www.newscientist.com/article/dn9930-introdu 3 George Marshall, Don’t Even Think About It: Why Our Brains Are ction-quantum-world (accessed 8 August 2016). Wired to Ignore Climate Change (Bloomsbury USA, 2015). 23 There are many architectures that can be proposed as candidates for 4 P.W. Anderson, “More Is Different,” Science 117, No. 4047, 393–396 quantum computing, of which measurement-based quantum com- (1972). putation is one—H. Briegel et al., “Measurement-Based Quantum Computation,” Nature Physics 5, No. 1, 19–26 (2009). Available at 5 Christos H. Papadimitriou, Computational Complexity: A Modern https://arxiv.org/abs/0910.1116 (accessed 8 August 2016). Approach (Pearson, 1993). 24 Hans J. Briegel and Robert Raussendorf, “Persistent Entanglement 6 Tor Nørretranders, “2011: What Scientific Concept Would Improve in Arrays of Interacting Particles,” Physical Review Letters 86, No. 5, Everybody’s Toolkit? Depth,” Edge (undated): www.edge.org/res 910–913 (2001). ponse-detail/11393 (accessed 14 May 2016). 25 I. Bloch, “Quantum Coherence and Entanglement with Ultra-Cold 7 Steven Johnson, Emergence: The Connected Lives of Ants, Brains, Gases in Optical Lattices,” Nature 453 (19 June 2008) pp. 1016–1022: Cities, and Software (London: Penguin, 2001). www.nature.com/nature/journal/v453/n7198/full/nature07126.html 8 Heather Barnett, artist website: www.heatherbarnett.co.uk (accessed (accessed 20 April 2016). 8 August 2016). 26 Barnett [8]; Tyson [9]; Steinkamp [10]. 9 Keith Tyson: www.pacegallery.com/exhibitions/11688/keith-tyson 27 David Rokeby, “Very Nervous System,” artist website: www.david -large-field-array (accessed 2 February 2019). rokeby.com/vns.html (accessed 23 October 2016). 10 Jennifer Steinkamp, artist website: www.jsteinkamp.com (accessed 23 October 2016). 28 Barad [15] p. 141. 11 Vienna University of Technology, “Shaken, Not Stirred: Control over 29 Barad [15] p. 138. Complex Systems Consisting of Many Quantum Particles,” Phys. 30 Barad [15] p. 137. Org (4 June 2014): www.phys.org/news/2014-06-shaken-complex -quantum-particles.html (accessed 20 April 2016). 31 Barad [15] p. 140. 12 N.J. Cerf, G. Leuchs and E.S. Polzik, eds., Quantum Information with 32 Seth Lloyd, “The Universe as a Quantum Computer” (2013): www Continuous Variables of Atoms and Light (Singapore: World Scien- ..org/pdf/1312.4455v1.pdf (accessed 20 April 2016). tific, 2007). 33 Barad [15] p. 141. 13 D. Gross, S.T. Flammia and J. Eisert, “Most Quantum States Are Too Entangled to Be Useful as Computational Resources,” Physi- 34 Roy Ascott, “Towards a Field Theory for Postmodernist Art,” inTele - cal Review Letters (2009): https://link.aps.org/doi/10.1103/Phys- matic Embrace: Visionary Theories of Art, Technology, and Conscious- RevLett.102.190501 (accessed 2 February 2019). Also see Miranda ness (Berkeley and Los Angeles: Univ. of California Press, 2003) Marquit, “Too Much Entanglement Can Render Quantum Comput- pp. 178–182; p. 178–179. ers Useless”: www.phys.org/news/2009-05-entanglement-quantum -useless.html#jCp (accessed 8 August 2016). 35 Barad [15] p. 143. 14 Mark Buchanan, “Quantum Minds: Why We Think Like Quarks,” 36 Barad [15] p. 142. New Scientist (5 September 2011): www.newscientist.com/article /mg21128285.900-quantum-minds-why-we-think-like-quarks (ac- 37 Ascott [34] p. 178. cessed 23 October 2016). 38 Barad [15] p. ix. 15 Karen Barad, Meeting the Universe Halfway: Quantum Physics and the Entanglement of Matter and Meaning (Durham, NC: Duke Univ. 39 Claire Bishop, Installation Art (London: Tate Publishing, 2005). Press, 2007). 40 Ascott [34] p. 179. 16 Arkady Plotnitsky, Complementarity (Durham, NC: Duke Univ. Press, 1994). Manuscript received 9 August 2016. 17 James Elkins, Six Stories from the End of Representation (Palo Alto, CA: Stanford Univ. Press 2008) p. 195. Libby Heaney’s practice and research draw primarily on 18 Elkins [17] p. 204. science and technology both as subjects and tools. Her work 19 Elkins [17] p. 215. is not media-specific but typically interactive, postdigital and dealing with complexity, systems and language. She currently 20 Alistair Rae, Quantum Physics: A Beginner’s Guide (London: One- lectures at the Royal College of Art, where she runs the More is world Publications, 2005); Michael Nielsen and Isaac Chuang, Quan- tum Computation and Quantum Information (Cambridge, U.K.: Different elective and the Systems Research Group in the School Cambridge Univ. Press, 2000). of Communications.

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