          'required': _("No file was submitted."),
          'invalid': _("The submitted data was not a file. Check the encoding type on the form."),
          'no_name': _("No filename could be determined."),
          'empty': _("The submitted file is empty."),
          'max_length': _('Ensure this filename has at most {max_length} characters (it has {length}).'),
      }
      use_url = api_settings.UPLOADED_FILES_USE_URL
  
      def __init__(self, *args, **kwargs):
          self.max_length = kwargs.pop('max_length', None)
 
</s> remove         'blank': _('This field may not be blank.'),
        'max_length': _('Ensure this field has no more than {max_length} characters.'),
        'min_length': _('Ensure this field has at least {min_length} characters.')
 </s> add         'blank': _("This field may not be blank."),
        'max_length': _("Ensure this field has no more than {max_length} characters."),
        'min_length': _("Ensure this field has at least {min_length} characters.") </s> remove         'max_length': _('Ensure this field has no more than {max_length} characters.'),
 </s> add         'max_length': _("Ensure this field has no more than {max_length} characters."), </s> remove     message = _('The fields {field_names} must make a unique set.')
    missing_message = _('This field is required.')
 </s> add     message = _("The fields {field_names} must make a unique set.")
    missing_message = _("This field is required.") </s> remove         'invalid': _('Date has wrong format. Use one of these formats instead: {format}.'),
        'datetime': _('Expected a date but got a datetime.'),
 </s> add         'invalid': _("Date has wrong format. Use one of these formats instead: {format}."),
        'datetime': _("Expected a date but got a datetime."), </s> remove         'invalid': _('Time has wrong format. Use one of these formats instead: {format}.'),
 </s> add         'invalid': _("Time has wrong format. Use one of these formats instead: {format}."),
        'max_length': _("Ensure this filename has at most {max_length} characters (it has {length})."),
          'required': _("No file was submitted."),
          'invalid': _("The submitted data was not a file. Check the encoding type on the form."),
          'no_name': _("No filename could be determined."),
          'empty': _("The submitted file is empty."),
        'max_length': _("Ensure this filename has at most {max_length} characters (it has {length})."),
      }
      use_url = api_settings.UPLOADED_FILES_USE_URL
  
      def __init__(self, *args, **kwargs):
          self.max_length = kwargs.pop('max_length', None)
keep keep keep keep replace keep keep keep keep keep
 use double quotes for user visible strings; end user visible strings in full stops; add some missing translation tags 
rest_framework/fields.py