old_contents: DT_FORMAT = '%Y-%m-%dT%H:%M:%S'
  """Date/time format string"""
  
  from datetime import datetime
  from datetime import timedelta
  
  
  def str_to_datetime(dt_str):
      """
      Convert a "Google String" (RFC3339) to a datetime object.
      @note: does not support the timezone (ignores it)!
  
      @param str: dt_str, datetime as string
      @return: datetime
      """
      return datetime.strptime(dt_str[:-6], DT_FORMAT)
  
  
  def num_working_days(start, end):
      """
      Calculate the number of working days in a given date range.
  
      TODO: does not take holidays into account
  
      @param start: datetime, start of range
      @param end: datetime, end of range
      @return: int, number of working days
      """
      # add one day to the end, since that's easier to calculate that way
      end = end + timedelta(days=1)
  
      # count whole weeks
      total = end - start
      weeks = (total.days) / 7
      wdays = weeks * 5
  
      # handle the rest
      start_num = start.weekday()
      end_num = end.weekday()
      if end_num < start_num:
          end_num += 7
      # count number of non-weekend days in the range from start to end
      rest = len([d for d in range(start_num, end_num) if d % 7 < 5])
      wdays += rest
  
      return wdays
  
new_contents: """
  Calendar related utility functions
  """
  
  DT_FORMAT = '%Y-%m-%dT%H:%M:%S'
  """Date/time format string"""
  
  from datetime import datetime
  from datetime import timedelta
  
  
  def str_to_datetime(dt_str):
      """
      Convert a "Google String" (RFC3339) to a datetime object.
      @note: does not support the timezone (ignores it)!
  
      @param str: dt_str, datetime as string
      @return: datetime
      """
      return datetime.strptime(dt_str[:-6], DT_FORMAT)
  
  
  def num_working_days(start, end):
      """
      Calculate the number of working days in a given date range.
  
      TODO: does not take holidays into account
  
      @param start: datetime, start of range
      @param end: datetime, end of range
      @return: int, number of working days
      """
      # add one day to the end, since that's easier to calculate that way
      end = end + timedelta(days=1)
  
      # count whole weeks
      total = end - start
      weeks = (total.days) / 7
      wdays = weeks * 5
  
      # handle the rest
      start_num = start.weekday()
      end_num = end.weekday()
      if end_num < start_num:
          end_num += 7
      # count number of non-weekend days in the range from start to end
      rest = len([d for d in range(start_num, end_num) if d % 7 < 5])
      wdays += rest
  
      return wdays
  
subject: add docstring