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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_line(line: str, context: RunContext) -> typing.Optional[str]: """ Filters out lines that match a given regex :param line: line to filter :type line: str :param context: run context :type context: _RunContext :return: line if it doesn't match the filter :rtype: optional str """

    if context.filters is not None:
        for filter_ in context.filters:
            if re.match(filter_, line):
                return None
    return line