from typing import Union


def has_output_type(cell, output_type: Union[set, str]):
    """
    Select cells that have a given output_type

    :param cell: Cell object to select
    :param output_type: Output Type(MIME type) to select: text/plain, text/html, image/png, ...
    :type output_type: str
    :return: a bool object (True if cell should be selected)
    """
    if isinstance(output_type, str):
        output_types = {output_type}
    else:
        output_types = set(output_type)

    return cell.has_output_type(output_types)