code: def set_start_datetime(self, value, timezone=None):
          
  
          if value is None:
              self.__start_datetime = None
              return
  
          try:
              self.__start_datetime = typepy.type.DateTime(
                  value, strict_level=typepy.StrictLevel.MIN, timezone=timezone
              ).convert()
          except typepy.TypeConversionError as e:
              raise ValueError(e)
docs: Set the start time of the time range.
  
          :param value: |param_start_datetime|
          :type value: |datetime|/|str|
          :raises ValueError: If the value is invalid as a |datetime| value.
  
          :Sample Code:
              .. code:: python
  
                  from datetimerange import DateTimeRange
                  time_range = DateTimeRange()
                  print(time_range)
                  time_range.set_start_datetime("2015-03-22T10:00:00+0900")
                  print(time_range)
          :Output:
              .. parsed-literal::
  
                  NaT - NaT
                  2015-03-22T10:00:00+0900 - NaT