How to calculate annotator distribution over annotations

This script helps to evaluate how many annotations do annotators have in the export snapshot:

import sys
import json
from collections import Counter

tasks = json.load(open(sys.argv[1]))

emails = []
for task in tasks:
  for annotation in task['annotations']:
    emails.append(annotation['completed_by']['email'])

c = Counter(emails)

for email, count in c.most_common():
  print(email, count)

print('Total', len(emails))