Support format=None for date/time fields

1 files changed, 6 insertions, 6 deletions

diff --git a/rest_framework/fields.py b/rest_framework/fields.py
index db7ceabb..cbd3334a 100644
--- a/rest_framework/fields.py
+++ b/rest_framework/fields.py
@@ -548,8 +548,8 @@ class DateField(Field):
     format = api_settings.DATE_FORMAT
     input_formats = api_settings.DATE_INPUT_FORMATS
 
-    def __init__(self, format=None, input_formats=None, *args, **kwargs):
-        self.format = format if format is not None else self.format
+    def __init__(self, format=empty, input_formats=None, *args, **kwargs):
+        self.format = format if format is not empty else self.format
         self.input_formats = input_formats if input_formats is not None else self.input_formats
         super(DateField, self).__init__(*args, **kwargs)
 
@@ -604,8 +604,8 @@ class DateTimeField(Field):
     input_formats = api_settings.DATETIME_INPUT_FORMATS
     default_timezone = timezone.get_default_timezone() if settings.USE_TZ else None
 
-    def __init__(self, format=None, input_formats=None, default_timezone=None, *args, **kwargs):
-        self.format = format if format is not None else self.format
+    def __init__(self, format=empty, input_formats=None, default_timezone=None, *args, **kwargs):
+        self.format = format if format is not empty else self.format
         self.input_formats = input_formats if input_formats is not None else self.input_formats
         self.default_timezone = default_timezone if default_timezone is not None else self.default_timezone
         super(DateTimeField, self).__init__(*args, **kwargs)
@@ -670,8 +670,8 @@ class TimeField(Field):
     format = api_settings.TIME_FORMAT
     input_formats = api_settings.TIME_INPUT_FORMATS
 
-    def __init__(self, format=None, input_formats=None, *args, **kwargs):
-        self.format = format if format is not None else self.format
+    def __init__(self, format=empty, input_formats=None, *args, **kwargs):
+        self.format = format if format is not empty else self.format
         self.input_formats = input_formats if input_formats is not None else self.input_formats
         super(TimeField, self).__init__(*args, **kwargs)