I suddenly get 'NameError' all the time

When I run any function checkio() or other function it would always say: NameError: ... is not defined. However, I am 100% sure that the function is defined just as it should.

For example like my code is like this:

def safe_pawns(pawns): return 0

And I call the function in the command line as: safe_pawns()

Then it says "NameError: name 'safe_pawns' is not defined"

Is there some other how you guys call the function in the command line or is this a bug?

Thanks!

From: https://checkio.org/mission/brackets/solve/

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