datetimerange: Allow datetime.datetime in addition to str (#4167)

Closes: #4166

Author: willywu

third_party/2and3/datetimerange/__init__.pyi

@@ -8,7 +8,7 @@ class DateTimeRange(object):
     end_time_format: str
     is_output_elapse: bool
     separator: str
-    def __init__(self, start_datetime: Optional[str] = ..., end_datetime: Optional[str] = ..., start_time_format: str = ..., end_time_format: str = ...) -> None: ...
+    def __init__(self, start_datetime: Optional[Union[datetime.datetime, str]] = ..., end_datetime: Optional[Union[datetime.datetime, str]] = ..., start_time_format: str = ..., end_time_format: str = ...) -> None: ...
     def __eq__(self, other) -> bool: ...
     def __ne__(self, other) -> bool: ...
     def __add__(self, other) -> DateTimeRange: ...
@@ -29,9 +29,9 @@ class DateTimeRange(object):
     def get_start_time_str(self) -> str: ...
     def get_end_time_str(self) -> str: ...
     def get_timedelta_second(self) -> float: ...
-    def set_start_datetime(self, value: Union[datetime.datetime, str], timezone: Optional[str] = ...) -> None: ...
-    def set_end_datetime(self, value: Union[datetime.datetime, str], timezone: Optional[str] = ...) -> None: ...
-    def set_time_range(self, start: Union[datetime.datetime, str], end: Union[datetime.datetime, str]) -> None: ...
+    def set_start_datetime(self, value: Optional[Union[datetime.datetime, str]], timezone: Optional[str] = ...) -> None: ...
+    def set_end_datetime(self, value: Optional[Union[datetime.datetime, str]], timezone: Optional[str] = ...) -> None: ...
+    def set_time_range(self, start: Optional[Union[datetime.datetime, str]], end: Optional[Union[datetime.datetime, str]]) -> None: ...
     def range(self, step: Union[datetime.timedelta, relativedelta]) -> Iterable[datetime.datetime]: ...
     def intersection(self, x: DateTimeRange) -> DateTimeRange: ...
     def encompass(self, x: DateTimeRange) -> DateTimeRange: ...