def describe_execution(executionArn=None):
    """
    Describes an execution.
    See also: AWS API Documentation
    
    
    :example: response = client.describe_execution(
        executionArn='string'
    )
    
    
    :type executionArn: string
    :param executionArn: [REQUIRED]
            The Amazon Resource Name (ARN) of the execution to describe.
            

    :rtype: dict
    :return: {
        'executionArn': 'string',
        'stateMachineArn': 'string',
        'name': 'string',
        'status': 'RUNNING'|'SUCCEEDED'|'FAILED'|'TIMED_OUT'|'ABORTED',
        'startDate': datetime(2015, 1, 1),
        'stopDate': datetime(2015, 1, 1),
        'input': 'string',
        'output': 'string'
    }
    
    
    """
    pass
