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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_blen(self):
 """Get the BPF buffer length"""


        try:
            ret = fcntl.ioctl(self.ins, BIOCGBLEN, struct.pack("I", 0))
            return struct.unpack("I", ret)[0]
        except IOError:
            warning("Unable to get the BPF buffer length")
            return