@classmethod
def set_ssm_client(cls, client):
    """Override the default boto3 SSM client with your own."""
    required_methods = 'get_parameters', 'get_parameters_by_path'
    for method in required_methods:
        if not hasattr(client, method):
            raise TypeError('client must have a %s method' % method)
    cls._ssm_client = client
