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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 generate_key(self, force=False):
 """ Creates a key file for this TaxPayer Creates a key file for this TaxPayer if it does not have one, and immediately saves it. Returns True if and only if a key was created. """

        if self.key and not force:
            logger.warning(
                'Tried to generate key for a taxpayer that already had one'
            )
            return False

        with NamedTemporaryFile(suffix='.key') as file_:
            crypto.create_key(file_)
            self.key = File(file_, name='{}.key'.format(uuid.uuid4().hex))
            self.save()

        return True