old_contents: import hashlib
  import datetime
  
  
  def get_gravatar_url(email):
      email_hash = hashlib.md5(email.lower().encode('utf-8')).hexdigest()
      return "https://www.gravatar.com/avatar/{}".format(email_hash)
  
  
  def next_weekday(date, weekday):
      days_ahead = weekday - date.weekday()
      if days_ahead <= 0: # Target day already happened this week
          days_ahead += 7
      return date + datetime.timedelta(days_ahead)
  
new_contents: import hashlib
  import datetime
  
  
  def get_gravatar_url(email):
      email_hash = hashlib.md5(email.lower().encode('utf-8')).hexdigest()
      return "https://secure.gravatar.com/avatar/{}".format(email_hash)
  
  
  def next_weekday(date, weekday):
      days_ahead = weekday - date.weekday()
      if days_ahead <= 0: # Target day already happened this week
          days_ahead += 7
      return date + datetime.timedelta(days_ahead)
  
subject: Update utils.py