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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_ids(ctx, param, value):
 """Validate a list of IDs and convert them to a list."""

    if not value:
        return None

    ids = [x.strip() for x in value.split(',')]
    for id_item in ids:
        if not id_item.isdigit():
            raise click.BadParameter('Non-numeric value "{0}" provided for an ID.'.format(id_item))

    return ids