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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def key( seq: Sequence, tooth: Callable[[Sequence], str] = ( lambda seq: str(random.SystemRandom().choice(seq)).strip() ), nteeth: int = 6, delimiter: str = ' ', ) -> str: """Concatenate strings generated by the tooth function."""

    return delimiter.join(tooth(seq) for _ in range(nteeth))