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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 file_source_hunks(self, filename):
 """ Like `CoberturaDiff.file_source`, but returns a list of line hunks of the lines that have changed for the given file `filename`. An empty list means that the file has no lines that have a change in coverage status. """

        lines = self.file_source(filename)
        hunks = hunkify_lines(lines)
        return hunks