def cont(X):
    """Returns True for all non-categorical columns, False for the rest.

    This is a helper function for OpenML datasets encoded as DataFrames simplifying the handling
    of mixed data types. To build sklearn models on mixed data types, a ColumnTransformer is
    required to process each type of columns separately.
    This function allows transformations meant for continuous/numeric columns to access the
    continuous/numeric columns given the dataset as DataFrame.
    """
    if not hasattr(X, "dtypes"):
        raise AttributeError("Not a Pandas DataFrame with 'dtypes' as attribute!")
    return X.dtypes != "category"