old_contents: from datetime import date, timedelta
  
  
  def get_date_from_now(nb_days):
      return date.today() - timedelta(days=nb_days)
  
  
  def get_date_diff(date_a, date_b):
      return abs((date_b - date_a).total_seconds())
  
new_contents: from babel.dates import format_datetime
  from datetime import date, datetime, timedelta
  
  
  def get_date_from_now(nb_days):
      return date.today() - timedelta(days=nb_days)
  
  
  def get_date_diff(date_a, date_b):
      return abs((date_b - date_a).total_seconds())
  
  
  def get_date_string_with_timezone(date_string, timezone):
      """
      Apply given timezone to given date and return it as a string.
      """
      date_obj = datetime.strptime(date_string, "%Y-%m-%dT%H:%M:%S")
      return format_datetime(
          date_obj,
          "YYYY-MM-DDTHH:mm:ss",
          tzinfo=timezone
      )
  
subject: Add helper to handle timezone in date strings