code: def check_event_coverage(patterns, event_list):
      
      proportions = []
      for pattern_list in patterns:
          proportion = 0
          for pattern in pattern_list:
              for node in pattern.nodes():
                  if node in event_list:
                      proportion += 1.0 / len(pattern_list)
                      break
          proportions.append(proportion)
      return proportions
docs: Calculate the ratio of patterns that were extracted.