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We all laugh. This hour of Radiolab asks why.

If you look closely, you'll find that humor has very little to do with it. We ask what makes us laugh, and how it affects us. Along the way, we tickle some rats, listen in on a baby's first laugh, talk to a group of professional laughers, and travel to Tanzania to investigate an outbreak of contagious laughter.


Amanda Aronczyk, JoAnne Bachorowski, Dr. Jaak Panksepp, Dr. Robert Provine, Barry Sanders and Tyler Stillman

Is Laughter just a Human Thing?

Aristotle thought that laughter is what separates us from the beasts, and that a baby does not have a SOUL, until the moment it laughs for the first time. Historian Barry Sanders, author of Sudden Glory, says that according to Aristotle, this moment of "human ensouling" is supposed to ...

Comments [45]

How Does Laughing Affect Us?

In this segment, we explore the rise and fall of a group of professional laughers hired to laugh for money on Fran Drescher's show "The Nanny." Then JoAnne Bachorowski, a psychologist at Vanderbilt University, says that giggling girls have more power than you think. She studies the sound of laughter, ...

Comments [32]

Contagious Laughter

We travel across the ocean and back to the year 1962, to a girl's boarding school on the outskirts of a rural village in Tanganyika (now Tanzania), where an epidemic of contagious laughter broke out. Producer Ellen Horne investigates and her search for an explanation brings us back to the ...

Comments [28]

Comments [77]

Nancy Gilbert from Avondale Estates GA

The "Laughing Box" always was and is creepy--it does not induce laughter! I feel a Stephen King novel in the making . . .

Nov. 16 2016 12:58 PM
Christina Sever from Oregon

One of you said that people don't laugh alone without radio, tv or other media inducing it. I was reading a book yesterday and laughed out loud. It immediately made me realize that it was a very good, very funny book if it could make me laugh out loud when I was alone, reading. Otherwise, your show is great. I try to never miss it. Thank goodness for podcasts.

Nov. 13 2016 06:55 PM
Tom from Colorado

I listened to the show on laughter with interest. But, I thought something was missing. All laughs, or all humor, may not be the same.

Nov. 12 2016 05:26 PM
Andy Leon from San Diego

Capuchin monkeys laugh.

Nov. 11 2016 11:15 PM
sarah latimer from Gloucester

Ok, first off, define your terms. As noted above, nervous laughter and humor are entirely different things. As both are from shared enjoyment, surprise, empathy, or myriad other reasons we laugh.

Secondly, blaming religion for insisting that we are unlike animals is disingenuous, esp after heavily featuring Aristotle. Resistance to realizing that we are animal comes in all shapes and forms.

Thirdly, you don't laugh when you are alone??? Really? I laugh on my own frequently, and not just when reading. I laugh when thinking, when seeing, when remembering, when surprised. Shallow analysis. Not worthy of your usual stuff.

But thanks for all you do. Esp CRISPR

Nov. 11 2016 11:10 AM
Christine Jones from La Crescenta

Your segment that asked about whether or not animals laugh reminded me of this video:

Nov. 10 2016 01:09 AM

Good episode, but I thought Robert Provine's thesis was completely ridiculous. The "social" aspect of laughter attributed to cocktail parties is more about nervous energy and social anxiety than it is about the evolution of the reason behind laughter. The people that laugh in these situations where "nothing is funny" are simply a certain brand of people that are insecure and make more noise to cover this insecurity than others. To base a study on such an ill-founded hypothesis shouldn't be considered science. Either that or he should've called the study "what we can learn from those who make the most noise in social situations."

I for one laugh when I'm alone all the time, and I've never laughed in my life unless something was funny to me.

Jun. 30 2016 05:14 PM
Don from Sweden

Great Show, I would like to give my opinion about the sounds you used. Please use a compressor to keep the volume of sounds at same level as your speech and why everyone is using so scary sounds in podcasts related to science or technology .etc.? I listened this podcast during my night time shift and got frightened alot of time because of the sounds you are used, eventhough the subject wasn't scary at all. Please try to use less scary sounds and don't play loudness war with the samples you use.

Sep. 24 2014 12:38 AM

Great episode!

Sep. 23 2014 08:38 PM
alexa from Media, PA

Thank you for highlighting the enormous health benefits of laughter! Need more laughter in your life? I tried Laughter Yoga and it changed my life.

I recently studied with the founder of Laughter Yoga, Dr. Madan Kataria in Bangalore, India, where I became a certified Laughter Yoga teacher.

I now lead a FREE Laughter Yoga Club. and share Laughter yoga at schools, senior centers, businesses and organizations.

Sep. 23 2014 02:07 PM
Alfred E. Neuman

Mad Magazine knew the power of laughers and infectious laughter back in the 1960's. They used it on their cardboard records that were included inside the magazine.

Youtube has them.

Meed the staff of Mad Magazine

Sep. 23 2014 12:12 AM

I have woken up from a dream in which I was laughing very loud/hard. Just saying. I guess the listener was "in my head" as they say in the podcast.

Sep. 22 2014 04:23 PM
Donna from DC

I am pretty sure there is a scientific explanation that researchers failed to uncover during the 1962 Tanzania mass laughter/hysteria outbreak. It is possible that what actually caused the affliction may have been a chemical spill, spray, or biological agent that may have been beyond the capacity of Tanzanian lab and medical services to detect. When considering the circumstances and overall tenuous nature of the political environment, the level of uncertainty surrounding that event, as well as the research and investigative efforts expended on determining the cause, is not unreasonable.

However, the idea that a country going through a state of "change" or "flux" due to changes in religious and social orders holds little water given a failure to replicate this scenario in other societies with similar circumstances the world over (as far as I am aware, anyway).

Sep. 21 2014 01:02 PM
Patrick from Port Townsend, WA

Even better:

The Self Beyond Itself: An Alternative History of Ethics, the New Brain Sciences, and the Myth of Free Will

Heidi M. Ravven

Sep. 20 2014 02:01 AM
Patrick from Port Townsend, WA

Panksepp has so much more to say. Get

The Archaeology of Mind: Neuroevolutionary Origins of Human Emotions (Norton Series on Interpersonal Neurobiology)

from your library.

We are them.

Sep. 20 2014 01:40 AM
Marko from Croatia

So, the guy said animals laugh and was laughed out of the room?

Jul. 26 2014 06:35 PM

It says in the bible laughter is good medicine for the soul. It makes us feel better. It heals the soul. It has a purpose. God is love and love to is a good thing.

Apr. 19 2014 12:09 PM
.alan from nc

it happened to me had nitrous oxide which is called laughing gas. but it wasnt the drug what happened was one girl started laughing so hard that her friends started laughing. it was one of those crazy snorting i cant breathe type of laugh. then her friends started laughing like her as well. then it was crazy everyone started to notice the crazy girls and laughing and then one by one thought it was so funny that they all started uncontrollably laughing. the guy selling nitrous was set up between two hotel started laughs in hampton vriginia. there were people on the porch like a motel watching the nitrous sellers and buyers stumbling. even the people who werent taking the nitrous but it was crazy it was uncontrollable literally twenty or thirty people rolling around the grass been around alot of drugs nver seen anyting like this i literally thought people were going to die of choking or heart atack. then some yelled police and everone stopped instantly it was nightmarish.

Apr. 17 2013 03:10 AM
Paul J. Stamler from St. Louis, MO, USA

Megg, you took the words right out of my mouth -- chimps are not our ancestors, any more than we are chimps' ancestors. The only thing I would add is that chimps have almost certainly moved genetically, as far away from our common ancestor as we have. (I'm assuming here that the genetic changes are random. Looking at changes which have been shaped by natural selection, we, or chimps, may have moved farther from the ancestor -- since we don't have a specimen of the ancestor, which has been extinct for a few million years, we don't know.) But your main point is right on the money: chimps are our cousins, not our ancestors.

Apr. 17 2013 12:18 AM
Cliff Callinan from Albany, NY

Terrific show. Suggest as a followup that you compile a bunch of different laughs and hold a survey to nominate the top ten.

Apr. 16 2013 08:26 PM
Stephane Delisle from CANADA

First, I love the show - thank you for doing what you do. Keep up the great work.
My wife and I were enjoying this episode, and I simply have to call out the biggest irony (for us anyway) within it: Part of the episode focused on the professional laughers used during the taping of Fran Drescher's "The Nanny"... HELLO!?! Fran, The Nanny! Her laugh has long been recognized as one of the all-time worst, most annoying laughs in television history.
I fully comprehend that RadioLab is great at dumbing-down the science and sharing great knowledge with listeners - it is fact-based, very interesting but also fun and sometimes light.
I simply had to write in as you must have consciously chosen not to at least make one wise-crack related to this irony. Thanks, I had to get this out there...

Apr. 14 2013 09:06 PM

During the episode you said you thought "birds sing because they are happy." Not so. They sing, or call, for species specific purposes related to their life cycles. For example, marking territory, "If you can hear this you are too close," to attract a mate, usually males do this, "hey, lady come check me out." Flock feeders sometimes have a sentinel bird posted to look out for predators while the others in the flock feed.The sentinel will give an alarm call if a predator is spotted. Parents use specific calls to their chicks.

Apr. 14 2013 02:38 PM

was anyone able to find a link to the Mike Nichols/Elaine May rehearsal?

Apr. 13 2013 09:49 PM
Evelyn Uyemura

I was surprised that no mention was made of a phenomenon in the Pentecostal Christian community a few years ago called "holy laughter." There's a Wikipedia page abut it:

Much like the Tanzania example, it was contagious bouts of extreme laughter that was associated with spiritual power, in this case, "Holy Ghost laughter."

Apr. 13 2013 07:07 PM
Jeigh Neither from Los Angeles

I have to both agree and disagree with the "we don't laugh when were alone" comment. I'm a writer. I crack myself up sometimes, and I am most often alone. However, the bigger truth is that we are never alone. We are like the Aspen tree (largest living organism on Earth...hint?) We are one. We are all tied together by a cosmic fabric our eyes can't see.

Not buying it?

Think of this...two things never actually touch. On an atomic level, the electrons won't allow it, so as you touch your arm, or leg, or whatever might inspire you, convince yourself that you're not. Convince yourself that you've never touched anything...

It's difficult, and not needed really, because it's the opposite that's actually true.

All is One. We are always touching each other.

It's hard to handle, but why keep lying to ourselves about it.

Apr. 13 2013 06:38 PM
Trixie from West Hollywood, CA

When my now 30 year old son was four months old, while changing him, I sneezed.
He laughed for the first time. I wept. He had become a human individual at
that moment.

Apr. 13 2013 06:11 PM
Ruth Fowler from Houston, Texas

I heard the show on laughter, and the speaker's comment that it's a social action, and people don't laugh if they are alone. I disagree with the remark because I have lived alone for years and find myself laughing aloud at parts/comments from The Daily Show, The Stephen Colbert Report, or The Jay Leno Show or in the morning when I read a newspaper comic strip.

Apr. 13 2013 04:39 PM
Sarah from Connecticut

Loved the show. Coincidentally, I did a blog post yesterday about professional laughers, known as "claques," who have been around since the time of Ancient Greece. Thought this might interest you:

Apr. 13 2013 04:23 PM
gibbs williams Ph.D. from Larchmont, New York

Excellent program. Support for your theory for the collective laughter event is that at weddings many people cry and at funerals many people laugh. What is similar about both is the often intense emotional stirrings most people naturally experience in the context of significant life defining events. In the book The Madness of Crowds evidence is abundant that when so called God fearing human beings get whipped up in a frenzy they can turn into an hysterical lynch mob.

Apr. 13 2013 01:10 PM

There's a saying, el que solo se ríe de sus maldades se acuerda, difficult to imagine that laughing alone is uncommon.

Apr. 13 2013 12:05 AM
Summer Daily from Indianapolis, IN

So there's something you guys didn't address, that I'm curious about. Tonight's episode focused on the sound of laughter: why we make those sounds and what they mean. However, you didn't address a silent laugh. My courtesy laugh is audible (much like the ones you played). However, when I find something absolutely hilarious, I laugh silently. My whole body shakes, and I can barely breathe, but no sound comes out. This doesn't fit with the theory that apes laugh to communicate that they are fine or just playing. Nor does it fit with the study of sound and how the individual pieces of a laughter each play a specific role. Has anyone thought about silent laughter and how it affects the results of studies done on audible laughter?

Apr. 12 2013 10:07 PM
Caitlin from Burbank CA

I laugh when I'm buy myself ALL the time. No media no other people but holy *** I just ran into a that's funny if only my friends were here to see me do this. So maybe it is social because I am laughing at how funny others would think it is.

Apr. 12 2013 06:55 PM

Great program on a fascinating subject! That said, another show really needs to be done on this topic. Science has learned a lot about laughter in the last five years. Answers to just about every question asked about laughter and humor, in this piece and in the scientific literature as a whole, can now be found at the following free, non-commercial site It's the most intuitive, comprehensive explanation you'll find anywhere.

Apr. 12 2013 06:12 PM
Melody from Davis, CA

I have been tickling my keeshond Casey for years, and delighting in his obvious laughter. I found it fascinating to hear the same cadence in the rat laughter, and now it's clear to me why I "instinctively" recognized Casey's response to tickling as laughter. What fun!!!

Apr. 12 2013 12:23 PM
Carol Fraser from Montreal

Great episode, but the heteronormativity of the segment on the girl's school in Africa was a bit frustrating. Not all teenage girls are into boys and want to get their attention - some are independent and self-confident! Furthermore it's really unfair to say that "boys just want to have sex" when they're teenagers. Such a stereotype only further contributes to an expectation of rampant sexuality that in our culture perpetuates itself in the form of rape and other abuses.

Mar. 01 2013 04:47 PM
faggz from fuck

go check out:

u will shit bricks

Jan. 31 2013 09:34 AM

wait, you dont laugh by your self ?!?! cumon, am kinda shocked

Sep. 21 2012 04:20 AM
Ben Link Collins from Taos, NM

Nurse With Wound's "The Ladies Home Tickler," Side B, has an exquisite sound collage of the Mike Nichols and Elaine May recording.

Jul. 09 2012 11:17 PM

I laugh alone now and then. With no pets around, and without imagining how it'd be if other people were there. I suppose it's not as common as laughing with other people, but those laughs can be pretty good, perhaps because they're often so unexpected.

Jun. 19 2012 05:16 AM
Jberg from Toronto, Ontario

Zara, when you are with your cat you are not alone and when you laugh at something you do because you imagine how it would seem if others were around then you are still applying a social setting to the scene and that ingredient seems as important as the actual act cause the laughter. Think about how when something funny happens and you are alone you usually want to tell/share it with someone else immediately.

Feb. 19 2012 09:33 AM

In this segment Jad says that he never laughs when he is alone.
I laugh when I am alone all the time, I get amused by little things. Like if I see my cat do something funny, or I do something that would be funny in any other circumstance.
Does anyone else do this?

Jan. 26 2012 11:13 PM

remember the scene on the train. well here is some contagious laughter from germany

Dec. 24 2011 05:20 PM

This is quite relevant to the laughter epidemic mentioned in the show :

Dec. 17 2011 09:18 AM
alfredboomslang from Planet Earth

Listen and try not to laugh:

Jun. 20 2011 07:39 PM
Neil from Canada

I thought it was interesting that they Nanny show hired people to laugh when many simply used laugh tracks.

Overall interesting topic

May. 31 2011 11:04 AM
John from Indiana

In the season 7 episode "Limits", in the segment about Ironman triathalete Julia Moss, her friend Wendy Ingraham is in the interview, and sometimes laughs at things Julia says. Her laugh sounds exactly like a sound chimps often make, but it's not the "panting" laugh.

Feb. 25 2011 09:33 AM
Lowell from Indiana

They never seem to take their speculation far enough for me; it is kind of amazing to think that apes 'laugh' as a signal for safety, good-will, a lack of fear and agression. It occures to me we laugh for exactly the same reason, we've just made it more complex and sophisticated. What is the most funny? Bad things are funny. From discomfort, awkwardness, all the way to pain and horror-- when one plays with these things, shows their absurdity, stupidity, irony-- somehow we can disarm them by laughing. It feeds us emotionally, by laughing we combat the terrors of the universe with this noise, it makes us feel safe in our ape heart.

Jan. 19 2011 11:35 AM
Colin from Edmonton, AB

Where did the sounds at approx: 21:50 come from? I love those noises.

Dec. 07 2010 03:32 PM
brittnany manigault from mt.Pleasant

hey how is this radio station and what else do you tlk about

Oct. 12 2010 02:54 PM

Perhaps you were laughing with your reflection - whenever I laugh alone I always seem to be imagining some unnamed person observing me o.O

Jan. 21 2010 12:39 AM
Jessica Mijnssen

Why do I laugh when it's inappropriate. I was hoping that the podcast would cover that, but sadly, it didn't.
Although, the laughing chimp may mean that when I'm inappropriately laughing at a funeral, the animal in me is telling others "I'm safe"

Feb. 28 2009 08:23 AM
John Simon

If you're interested in a gaining a new appreciation for this incredible behavior, you might check out my new book Why We Laugh: A New Understanding. It introduces the first and only comprehensive theory to explain the human laugh response—for every individual, every laugh, and every context. This new conceptual model reveals the essential qualities that make some thing or event appear amusing. It explains why we spend so much time and energy soliciting the laughter of others; why we are attracted to those who inspire our own; and why the laugh response varies among individuals and cultures, as well as over the course of an individual’s lifetime. The theory offers new insights into laughter’s most probable evolutionary origin. And it answers difficult questions pertaining to the ridiculing humor of bullies, laughter’s contagious quality, our sense of humor, and what laughter says about us—both as individuals and as a species.

If you have questions, this book has the answers. Learn more at

Aug. 28 2008 08:20 PM

You guys might enjoy this (it's a guy who leaves a message to his boss to let him know he's going to be late, and while leaving the message, a hilarious situation ensues):

Jul. 15 2008 04:42 PM
Jo from London

Yes, I find myself on public transport, or just walking down the road, occasionally trying not to giggle if an amusing thought has snuck in. It's not that socially acceptable to walk around London with a big grin on your face so the effort of trying to look normal probably makes me giggle more :)

I laugh out loud at the television if something amusing is on - and I'm by myself there too.

Apr. 20 2008 05:59 AM

I definitely laugh when I'm alone from time to time. But there's always that moment of pure self-awareness in the middle of the laugh when I've just realized that I'm completely alone. My laughter abruptly stops and I can feel my cheeks turning bright red. Where did I get the idea that laughing alone is such bad thing!?

Apr. 13 2008 02:30 AM

I do that and much more. I laugh, talk, argue, etc. It's fun and concerning :-)

Apr. 12 2008 03:30 PM
Mark Mascolino

Absolutely. It certainly easier to laugh with others but when something is truly funny I laugh out loud. Doing this while listening to a podcast and walking down the hall or the street does however receive some strange looks because they aren't in on the joke.

Mar. 30 2008 01:04 PM

The whole rats laughing thing was a bit ridiculous. The behavior described by the rats seemed a lot more like the behavior of cats when they want to be stroked. Since when is laughing the same as purring? There wasn't a lot of evidence either way, but based on the explanations in the show, these rats were far more likely "purring." I think it's pretty irresponsible of a science show to not mention this possibility.

Mar. 03 2008 02:43 AM

I really enjoyed the show, but I have to disagree with one part. When you talk about the chimps, you assert that no one ever laughs by themselves. Well that's simply not true. Haven't you ever just had a funny thought that made you laugh as you're walking down the street? Every written something down that made you laugh? Maybe I'm just some wacky loner, but I feel like I laugh on my own fairly regularly.

Thanks for such a great show. I'm thrilled to be getting full episodes again.

Feb. 28 2008 08:55 AM

Listened to the show today while taking a sunset walk through the dunes of The Hague and along the beach and found myself laughing a lot. Must have looked weird to the assorted cyclists, runners or dogwalkers. But you must know this: laughing is therapeutic and there are even laughter guru's and laughter workshops, courses and what have you.
I work with little kids (6-7 yrs old) and am planning to have them listen to some of the laughter on the show. Let's see what happens.

Feb. 27 2008 02:00 PM

The African laughing attacks were absolutely fascinating. I have to say though, your final explanation is as irrational as the caterpillar explanation.

Feb. 27 2008 01:41 PM


It's so glad to have you back.

As Robert said, DELIGHTFUL.

Feb. 27 2008 02:51 AM

For Robert, I hope he finds it delightful:

Feb. 27 2008 02:31 AM

I love every episode of the show and especially one about laughter. This one hits close to home. I have laughing attacks multiple times a day for no reason. Even in sad situations they come upon me. I have learned to semi control them into an odd smirk but if I let them go I can laugh uncontrollably for a minute or two as well as feeling a sort of state of euphoria. It is really weird but cool and have never come across anyone else who deals with this before. So yeah thought I would add that.

Feb. 26 2008 11:21 PM

Oops - first link missing last digit.

Feb. 26 2008 06:45 PM
Peet (Amsterdam, NL)

Hi Guys, I listen to your podcast on my 50 minutes bike ride to my work. I have to say: I just beamed all through the podcast. There are some folks in Amsterdam that are probably wondering what that smiling guy on the bike was laughing about ...
Any ways, grrrrreat show, love the content and L.O.V.E. the sound (being a sound'o phile myself) and the neat tricks with music and minimal music ... I have to say: AWESOME (sorry robbert). Keep them coming!

Feb. 26 2008 03:50 PM

"Is there something that makes sense about young girls breaking into uncontrollable giggles and laughter fits?"

As a school teacher, my response is a resounding "Well, DUH!!!"

Try teaching a room full of adolescents when one starts to laugh OR cry. For the girls, I've witnessed it brought on by any extreme show of emotion. For the boys, all it takes is an occurrence of any natural bodily function.

Feb. 26 2008 03:10 PM
Peggy Carey

Listening to the program on laughter, I was reminded of the time that I,as Mayor of Montrose, Colorado, began laughing as I read the agenda. There was nothing funny about the agenda, but for some reason I was compelled to laugh. Once I began, the laughter fed on itself and soon tears were running down my face. My whole City Council was looking at me in astonishment, but the audience was soon caught up and began laughing too. I finally had to hand the agenda to the Mayor Pro Tem and excuse myself. To this day I can't remember what struck me as funny, but I can remember not being able to catch my breath

Feb. 26 2008 01:29 PM
Sean Ward

Hey there! Listening to the episode on laughter, I noticed that the African laughing 'disease' happened at about the same time that Beatlemania erupted elsewhere in the world, and there were all of these girls screaming uncontrollably where before they were expected to remain quiet and composed. Perhaps this is a connection worth exploring? It seems like there was some pent-up energy out there in the world that burst forth all at once at about that time.

Feb. 26 2008 12:10 PM

That is all.

Feb. 26 2008 11:33 AM

I love, love, love Radiolab. It's great to have you back. I've listened to the first three seasons several times to tide me over until this season started. I have one comment on the laughter episode however: Chimpanzees are not our ancestors, they are our "cousins." We did not get any traits from chimpanzees, but rather from our common ancestor. It's an important distinction to make, as creationists love to seize on the idea that we could not possible be descended from monkeys. Thanks and keep up the great work.

Feb. 26 2008 10:45 AM
Patrick Hite

You helped brighten an otherwise dreary day here in Virginia when I opened my iTunes this morning and a new, full episode of Radiolab began to download. It will help me get through the day at work. I've missed you guys. Glad to have some new shows on the way. Keep up the great work.

Feb. 26 2008 10:14 AM

I believe Aristotle might not have been too far off on the 40 days theory. He was not aware, though, of evolution (or human devolvement).

Recently, NPR's Morning Edition featured a story in which it was discovered that kids can no longer stand still (like they could 60 years ago). I propose that infants have devolved to not have an understanding of humor until about their 90th day of existence.

The human species is getting dumber as machines do more and attention spans grow shorter.

Feb. 26 2008 09:03 AM

everything's ok scotty! check your podcast, it should be up now.

Feb. 26 2008 12:04 AM

I've been checking your section at the iTunes store for days now...any plans to put the latest podcast there? To download the MP3 from this site takes AGES, even with a cable modem.

I'm so glad you're new programs are here and can't wait 'til I can hear them!

Feb. 25 2008 11:24 PM

The last two MP3s don't exist, or perhaps I can't hear something, or something is wrong.

Everything okay Radiolab?

Feb. 25 2008 09:19 PM
Alfred Lopez

My wife Sherred and I have listeded to the show for some time now...I think that we started listening sometime during the season two run.

I have to say that I, rather we are completely enchanted by the show. It is something that we look forward to.

The Lab is truly one of the best programs out there. Now that that part is out of the way... Because you know you have to address that first and foremost,

HURRY GUYS! The world is waiting Season 4.

The "IF" segment made my day. Thanks again.

Alfred (Fort Worth, Texas)

Feb. 15 2008 03:07 PM

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