new_contents: import logging
  import migrations
  
  logging.basicConfig()
  
  log = logging.getLogger()
  
  conn = migrations.connect()
  
  cur = conn.cursor()
  
  def drop_index(table, idx):
      cur.execute("SHOW INDEX FROM %s WHERE KEY_NAME='%s'" % (table, idx))
      if cur.fetchone():
          cur.execute("DROP INDEX %s ON %s" % (idx, table))
  
  drop_index("planner_metrics", "idx_planner_metrics_root_wf_uuid")
  cur.execute("create index idx_planner_metrics_root_wf_uuid on planner_metrics(root_wf_uuid)")
  
  drop_index("planner_metrics", "idx_planner_metrics_ts")
  cur.execute("create index idx_planner_metrics_ts on planner_metrics(ts)")
  
  conn.commit()
  cur.close()
  
subject: Add migration script to add indexes