Count all jobs of certain name that has certain string in their last run

stats-by-logs.groovy

job_name="some-job" //I have multiple jobs with the same simple name under multiple folders
lookup_string="something inside the log" // the line we want to look for 
instance  = Jenkins.instance
def jobs = instance.allItems.findAll{it.name==job_name}
count = 0
for (job in jobs){
  lastRun = job.lastCompletedBuild
  lastBuildLog = lastRun.log
  if (lastBuildLog.contains(lookup_string)){
    println job.fullName + " " + instance.rootUrl + lastRun.url
    count = count + 1
  }
}
println "${count} out of ${jobs.size}"