I think the warning was helpful; it just had confusing wording.

Instead of: """
>>> def f():
...  False
...
<stdin>:2: SyntaxWarning: ignore constant statement
"""

perhaps: """
>>> def f():
...  False
...
<stdin>:2: SyntaxWarning: ignoring constant statement
"""

or even: """
>>> def f():
...  False
...
<stdin>:2: SyntaxWarning: ignoring unused constant 'False'
"""