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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def validate_page_size(ctx, param, value):
 """Ensure that a valid value for page size is chosen."""

    # pylint: disable=unused-argument
    if value == 0:
        raise click.BadParameter("Page size must be non-zero or unset.", param=param)
    return value