Reviewer comments

Author: jbrockmendel

pandas/_libs/tslib.pyx

@@ -857,10 +857,6 @@ class NaTType(_NaT):
     def __reduce__(self):
         return (__nat_unpickle, (None, ))
 
-    def total_seconds(self):
-        # GH 10939
-        return np.nan
-
     @property
     def is_leap_year(self):
         return False
@@ -3893,8 +3889,7 @@ _nat_methods = ['date', 'now', 'replace', 'to_pydatetime',
                 'today', 'round', 'floor', 'ceil', 'tz_convert',
                 'tz_localize']
 _nan_methods = ['weekday', 'isoweekday']
-_implemented_methods = [
-    'to_datetime', 'to_datetime64', 'isoformat', 'total_seconds']
+_implemented_methods = ['to_datetime', 'to_datetime64', 'isoformat']
 _implemented_methods.extend(_nat_methods)
 _implemented_methods.extend(_nan_methods)