“How do you tell a male door from a female door?”/“One’s got a ding-dong, the other has knockers.”

A door riddle (containing sex slang) is:
 
Q: How do you tell a male door from a female door?
A: One’s got a ding-dong, the other has knockers.
 
The joke was posted on Twitter by Aman on September 25, 2017. It was posted on Reddit—Dadjokes on January 10, 2021.
 
       
Twitter
Aman
@passionate_ink_
How do you tell a male door from a female door?
One’s got a ding-dong, the other has knockers
11:17 PM · Sep 25, 2017·Twitter for Android
   
Twitter
$w@&&u™
@IamDelveckio
How do you tell a male door from a female door?
One’s got a ding-dong, the other has knockers
7:42 PM · Sep 28, 2017·Facebook
   
Twitter
Liam
@LiamCaulfield26
How do you tell a male door from a female door?
One’s got a ding dong, the other has knockers.
12:50 PM · Jul 27, 2019·Twitter for Android
 
Reddit—3amjokes
Posted by u/VERBERD September 19, 2020
How do you tell a male door from a female door?
One’s got a ding dong, the other has knockers.
 
Reddit—Dadjokes
Posted by u/VERBERD January 10, 2021
How do you tell the difference between a male door and a female door?
One has a ding-dong and the other has knockers.
COMMENTS
Animancer
They both have knobs though? :(