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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 clear(self):
 """ Clear a breakpoint by removing it from all lists. """

        del IKBreakpoint.breakpoints_by_file_and_line[self.file_name, self.line_number]
        IKBreakpoint.breakpoints_by_number[self.number] = None
        IKBreakpoint.breakpoints_files[self.file_name].remove(self.line_number)
        if len(IKBreakpoint.breakpoints_files[self.file_name]) == 0:
            del IKBreakpoint.breakpoints_files[self.file_name]
        IKBreakpoint.update_active_breakpoint_flag()