def pipeline_splitting_rule(val_size = 0.2, test_size = 0.2, random_state = 13):
    """Setup percentage of train, validate, and test of each pipeline's dataset in Pipeline Cluster Traversal Experiments.
    
    Parameters
    ----------
    val_size : float, default = None
        Value within [0~1]. Percentage of validate data.
    test_size : float, default = None
        Value within [0~1]. Percentage of test data.
    random_state : int, default = 13
        Random state value.
    Returns
    -------
    Deliver the percentage values to splitting tool function.

    """
    custom_val_size,custom_size,custom_random_state = val_size, test_size, random_state
    return(custom_val_size,custom_size,custom_random_state)