Intended behavior of from_shorthand()?

[CookieComputing]

Playing around with the parameters of from_shorthand(), we can see that the method breaks down when given bogus values (barring the second example)

>>> intervals.from_shorthand("A","#")
False
>>> intervals.from_shorthand("A","3")
'C#'
>>> intervals.from_shorthand("A","foo")
False
>>> intervals.from_shorthand("As","foo")
False
>>> intervals.from_shorthand("Asasdf","foo")
False

Is this really intended behavior? From the previous tutorials, it would make sense if these inputs raised exceptions.