docstr: Return human-readable information on rule stats
docstr_tok: ["Return","human-readable","information","on","rule","stats"]
code: def statistics_info(cls):
      """Return human-readable information on rule stats"""
      if not cls.STATS:
          LOGGER.error("No rule statistics to return")
          return
  
      max_rule_name_len = max([len(rule) for rule in cls.STATS])
  
      stat_lines = [
          "{rule: <{pad}}{stat}".format(
              rule=rule, pad=max_rule_name_len + 4, stat=stat
          )
          for rule, stat in sorted(
              iter(cls.STATS.items()), key=lambda k_v: (k_v[1], k_v[0])
          )
      ]
  
      return "Rule statistics:\n\n{}".format("\n".join(stat_lines))
  
file_path: streamalert/streamalert/shared/stats.py
imports: from collections import defaultdict
  import time
  from streamalert.shared.logger import get_logger
label_desc: Use image node_id 3 for calling the RuleStatisticTracker obj's underlying member method code with example usage: obj.statistics_info(cls) and returns: str