#!/bin/bash
s='{"_id":{"$oid":"5a62094b2213930f39856faa"},"zip":"68137","visit_date":{"$date":"2017-11-28T15:36:00.000Z"},"phone":"402-000-0819","city":"Omaha","state":"NE","gender":"female","dob":{"$date":"2018-01-19T00:00:00.000Z"},"firstname":"Joshua","user_ip":"42.668.23.195","lastname":"Maestle","done":1.0
{"_id":{"$oid":"5a62094b2213930f39856fb4"},"zip":"85013","visit_date":{"$date":"2017-11-28T11:32:00.000Z"},"city":"Phoenix","state":"AZ","gender":"male","dob":{"$date":"2018-01-19T00:00:00.000Z"},"firstname":"Andre","lastname":"Lippens","done":1.0
{"_id":{"$oid":"5a62094b2213930f39856fbc"},"zip":"70535","visit_date":{"$date":"2017-11-28T17:07:00.000Z"},"phone":"000-305-1888","city":"Eunice","state":"LA","gender":"male","user_ip":"12.158.33.145","dob":{"$date":"2018-01-19T00:00:00.000Z"},"firstname":"Derek","lastname":"Moore"'
sed -En 's/.*"user_ip":"([^"]*).*|.*/\1/p' <<< "$s"

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