text: #!/usr/bin/env python
  
  import os
  import sys
  
  # Usage
  if len(sys.argv) is not 2:
      exit("Usage:\n\t" + sys.argv[0] + "colname_1,colname_2,colname_3 <input.tsv> output.tsv\n\nInput was:\n\tA tab-separated values (TSV) file")
  
  # argv
  c = sys.argv[1] # column name, e.g. 'participant_id,Mutect2_passed_combined_vcf,Mutect2_passed_combined_vcf_index'
  
  c = c.split(',')
  
  # main
  l = sys.stdin.readline()
  l = l.strip('\n').split('\t')
  h = dict((map(reversed, enumerate(l)))) # column name:indices
  ci = [h[cx] for cx in c] # column name indices
  
  lc = [l[cix] for cix in ci]
  sys.stdout.write('\t'.join(lc) + '\n') # column name indices
  
  for l in sys.stdin:
      l = l.strip('\n').split('\t')
      lc = [l[cix] for cix in ci]
      sys.stdout.write('\t'.join(lc) + '\n') # column name indices
  
  ### The End ###
  