Looking for a way to de-reference a bash var wrapped in a python command call
Question: I'm trying to find a way to de-reference goldenClusterID to use it in an AWS
CLI command to terminate my cluster. This program is to compensate for dynamic
Job-Flow Numbers generated each day so normal Data Pipeline shutdown via
schedule is applicable. I can os.system("less goldenClusterID") all day and it
gives me the right answer. However, it won't give up the goodies with a
straight de-ref. Suggestions?

    
    
    from __future__ import print_function
    
    import json
    import urllib
    import boto3
    import commands
    import os
    import re
    import datetime
    import awscli
    
    foundCluster = ""
    rawClusterNum = ""
    mainClusterNum = ""
    goldenClusterID = ""
    
    #   Next, we populate the list file with clusters currently active
    os.system("aws emr list-clusters --active >> foundCluster")
    #   We search for a specific Cluster Name
    os.system("fgrep 'AnAWSEMRCluster' foundCluster")
    os.system("grep -B 1 DrMikesEMRCluster foundCluster >> rawClusterNum")
    #   Look for the specific Cluster ID in context with it's Cluster Name
    os.system("fgrep 'j-' rawClusterNum >> mainClusterNum")
    #   Regex the Cluster ID from the line
    os.system("grep -o '\j-[0-9a-zA-Z]*' mainClusterNum >> goldenClusterID")
    #   Read the Cluster ID from the file and run AWS Terminate on it
    os.system("aws emr describe-cluster --cluster-id %s" % goldenClusterID")
    os.system("aws emr terminate-clusters --cluster-ids goldenClusterID")
    os.system("rm *")
    


Answer: Never mind, I figured it out. Too much coffee and not enough sleep. The answer
is to use: goldkeyID=open('goldenClusterID', 'r').read() os.system("aws emr
describe-cluster --cluster-id %s" % goldkeyID)

