“A guy walks into a bar…” is a typical form of what has been called the “bar joke.” A snake version about “walking” into a bar is:
   
“A snake walks into a bar. The bartender says, ‘How did you do that?’”
     
“A snake walks into a bar. Hah!” was cited in 2007 and “A snake walks into a bar. Waaaa?” was cited in 2008. “A snake walks into a bar. The barman says ‘how did you manage that? You’ve got no legs’” was cited on Twitter on April 14, 2011.
 
 
Pine for Pine   
FRIDAY, NOVEMBER 30, 2007
My Top Ten “Guy Walks Into a Bar” Jokes
POSTED BY FRANK CIMATU AT 11:39 AM
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7) A snake walks into a bar. Hah! 
 
Loosening Up, Letting Go, & Learning to Live Again
FRIDAY, OCTOBER 17, 2008
Send the Hate Mail
(...)
A snake walks into a bar. Waaaa?
 
Twitter   
Carly
‏@BoBarly
A snake walks into a bar. Wait, whaaaaa? #badjoke
7:25 AM - 3 May 2009
 
Twitter
Colin Tubb
‏@thecolintubb
@DanGalano A snake walks into a bar and everyones confused since snakes can’t walk but its a bar that supports equality so he’s still served
2:27 AM - 17 Feb 2011
 
Twitter 
prosciutto princess
‏@skiddycoot
A snake walks into a bar. Waaaa?
3:07 AM - 9 Apr 2011
 
Twitter
Brans Talgurn
‏@rrndhh
A snake walks into a bar. The barman says “how did you manage that? You’ve got no legs.”
2:16 PM - 14 Apr 2011
 
reddit
A snake walks into a bar
submitted December 3, 2015 by mtndew069
And the bartender asks “How did you do that?”
     
reddit
Snake walks into a bar.
submitted May 7, 2016 by CalmPc
And the bartender says ‘‘How did you do that?’‘
 
Twitter
emma wooten
‏@emmawootenn
so a snake walks into a bar and the bar tender says “how the fuck did u do that”
11:15 PM - 7 May 2016