inefficient way to code a sorted list of ip address integers to a range of integers

iptogeo.py

import sys, csv

idx = 0

with open('ipintegers_sorted.csv','r') as ipcsvinput:
    with open('geoiplite_sorted.csv','r') as geoipcsvinput:
        ipreader = csv.DictReader(ipcsvinput, delimiter=',', fieldnames = ("ipstring","ipinteger") )
        geoipreader = list(csv.DictReader(geoipcsvinput, delimiter=',', fieldnames = ("network_start_ip","network_last_ip","network_start_integer","network_last_integer","geoname_id","is_satellite_provider","is_anonymous_proxy","postal_code","latitude","longitude")))
        for iprow in ipreader:
            ipinteger = int(iprow['ipinteger'])
            ipstring = iprow['ipstring']
            for geoiprow in geoipreader[idx:]:
                geoipstartstring = geoiprow['network_start_ip']
                geoiplaststring = geoiprow['network_last_ip']
                geoipstartinteger = int(geoiprow['network_start_integer'])
                geoiplastinteger = int(geoiprow['network_last_integer'])
                geoiplatitude = geoiprow['latitude']
                geoiplongitude = geoiprow['longitude']
                geoipgeonameid = geoiprow['geoname_id']
                geoippostalcode = geoiprow['postal_code']
                if geoipstartinteger <= ipinteger <= geoiplastinteger:
                    print(ipstring,ipinteger,geoiplatitude,geoiplongitude,geoipgeonameid,geoippostalcode,sep=",")
                    break
                elif geoipstartinteger < ipinteger:
                    idx += 1
                    continue