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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 _detect(self):
 """Use the netifaces module to detect ifconfig information."""

        theip = None
        try:
            if self.opts_family == AF_INET6:
                addrlist = netifaces.ifaddresses(self.opts_iface)[netifaces.AF_INET6]
            else:
                addrlist = netifaces.ifaddresses(self.opts_iface)[netifaces.AF_INET]
        except ValueError as exc:
            LOG.error("netifaces choked while trying to get network interface"
                      " information for interface '%s'", self.opts_iface,
                      exc_info=exc)
        else:  # now we have a list of addresses as returned by netifaces
            for pair in addrlist:
                try:
                    detip = ipaddress(pair["addr"])
                except (TypeError, ValueError) as exc:
                    LOG.debug("Found invalid IP '%s' on interface '%s'!?",
                              pair["addr"], self.opts_iface, exc_info=exc)
                    continue
                if self.netmask is not None:
                    if detip in self.netmask:
                        theip = pair["addr"]
                    else:
                        continue
                else:
                    theip = pair["addr"]
                break  # we use the first IP found
        # theip can still be None at this point!
        self.set_current_value(theip)
        return theip