def get_num_feats(data=None):
    """
    Returns the numerical features in a data set

    Parameters:
    -----------
        data: DataFrame or named Series 

    Returns:
    -------
        List:
            A list of all the numerical features in a dataset.
    """
    if data is None:
        raise ValueError("data: Expecting a DataFrame or Series, got 'None'")
    num_features = data.select_dtypes(exclude=['object', 'datetime64']).columns
    return list(num_features)
