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# Exclamation Mark (`!`)
    
## `! 𝕩`: Assert
    
Throw an error if `𝕩` is not 1.
    
           ! 1

           ! 2

           ! "hello"


    
    
## `𝕨 ! 𝕩`: Dyad
    
Throw an error with message `𝕨` if `𝕩` is not 1.
    
           "hi" ! 1

           "two" ! 2

           "hello error" ! "hello"