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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 iam(cls, account_name, api_key, **kwargs):
 """ Create a Cloudant client that uses IAM authentication. :param account_name: Cloudant account name. :param api_key: IAM authentication API key. """

        return cls(None,
                   api_key,
                   account=account_name,
                   auto_renew=kwargs.get('auto_renew', True),
                   use_iam=True,
                   **kwargs)