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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 filter_skiplines(code, errors):
 """Filter lines by `noqa`. :return list: A filtered errors """

    if not errors:
        return errors

    enums = set(er.lnum for er in errors)
    removed = set([
        num for num, l in enumerate(code.split('\n'), 1)
        if num in enums and SKIP_PATTERN(l)
    ])

    if removed:
        errors = [er for er in errors if er.lnum not in removed]

    return errors