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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(self, predicate: Callable[[FileLine], 'FileLineSet'] ) -> 'FileLineSet': """ Returns a subset of the file lines within this set that satisfy a given filtering criterion. """

        filtered = [fileline for fileline in self if predicate(fileline)]
        return FileLineSet.from_list(filtered)