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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 get_breaks_lno(self, filename):
 """List all line numbers that have a breakpoint"""

        return list(
            filter(
                lambda x: x is not None, [
                    getattr(breakpoint, 'line', None)
                    for breakpoint in self.breakpoints
                    if breakpoint.on_file(filename)
                ]
            )
        )