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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 __sum(self, line):
 """Return the IRQ sum number. IRQ line samples: 1: 44487 341 44 72 IO-APIC 1-edge i8042 LOC: 33549868 22394684 32474570 21855077 Local timer interrupts FIQ: usb_fiq """

        splitted_line = line.split()
        try:
            ret = sum(map(int, splitted_line[1:(self.cpu_number + 1)]))
        except ValueError:
            # Correct issue #1007 on some conf (Raspberry Pi with Raspbian)
            ret = 0
        return ret