diff --git a/pandas/tests/scalar/period/test_period.py b/pandas/tests/scalar/period/test_period.py
index 3bdf91cbf838b..73371c48f9370 100644
--- a/pandas/tests/scalar/period/test_period.py
+++ b/pandas/tests/scalar/period/test_period.py
@@ -1044,6 +1044,7 @@ def test_add_sub_nat(self):
         assert NaT - p is NaT
 
         p = Period("NaT", freq="M")
+        assert p is NaT
         assert p + NaT is NaT
         assert NaT + p is NaT
         assert p - NaT is NaT
@@ -1284,6 +1285,7 @@ def test_add_offset_nat(self):
         # freq is DateOffset
         for freq in ["A", "2A", "3A"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [offsets.YearEnd(2)]:
                 assert p + o is NaT
                 assert o + p is NaT
@@ -1300,6 +1302,7 @@ def test_add_offset_nat(self):
 
         for freq in ["M", "2M", "3M"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [offsets.MonthEnd(2), offsets.MonthEnd(12)]:
                 assert p + o is NaT
                 assert o + p is NaT
@@ -1317,6 +1320,7 @@ def test_add_offset_nat(self):
         # freq is Tick
         for freq in ["D", "2D", "3D"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [
                 offsets.Day(5),
                 offsets.Hour(24),
@@ -1340,6 +1344,7 @@ def test_add_offset_nat(self):
 
         for freq in ["H", "2H", "3H"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [
                 offsets.Day(2),
                 offsets.Hour(3),
@@ -1439,6 +1444,7 @@ def test_sub_offset_nat(self):
         # freq is DateOffset
         for freq in ["A", "2A", "3A"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [offsets.YearEnd(2)]:
                 assert p - o is NaT
 
@@ -1453,6 +1459,7 @@ def test_sub_offset_nat(self):
 
         for freq in ["M", "2M", "3M"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [offsets.MonthEnd(2), offsets.MonthEnd(12)]:
                 assert p - o is NaT
 
@@ -1468,6 +1475,7 @@ def test_sub_offset_nat(self):
         # freq is Tick
         for freq in ["D", "2D", "3D"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [
                 offsets.Day(5),
                 offsets.Hour(24),
@@ -1489,6 +1497,7 @@ def test_sub_offset_nat(self):
 
         for freq in ["H", "2H", "3H"]:
             p = Period("NaT", freq=freq)
+            assert p is NaT
             for o in [
                 offsets.Day(2),
                 offsets.Hour(3),
@@ -1511,6 +1520,7 @@ def test_sub_offset_nat(self):
     @pytest.mark.parametrize("freq", ["M", "2M", "3M"])
     def test_nat_ops(self, freq):
         p = Period("NaT", freq=freq)
+        assert p is NaT
         assert p + 1 is NaT
         assert 1 + p is NaT
         assert p - 1 is NaT
diff --git a/pandas/tests/scalar/timestamp/test_timestamp.py b/pandas/tests/scalar/timestamp/test_timestamp.py
index 652dd34ca7ce2..f9fa80644d4b9 100644
--- a/pandas/tests/scalar/timestamp/test_timestamp.py
+++ b/pandas/tests/scalar/timestamp/test_timestamp.py
@@ -202,8 +202,6 @@ def test_constructor(self):
         base_expected = 1404205200000000000
 
         # confirm base representation is correct
-        import calendar
-
         assert calendar.timegm(base_dt.timetuple()) * 1000000000 == base_expected
 
         tests = [
@@ -275,8 +273,6 @@ def test_constructor_with_stringoffset(self):
         base_expected = 1404205200000000000
 
         # confirm base representation is correct
-        import calendar
-
         assert calendar.timegm(base_dt.timetuple()) * 1000000000 == base_expected
 
         tests = [
diff --git a/pandas/tests/scalar/timestamp/test_timezones.py b/pandas/tests/scalar/timestamp/test_timezones.py
index 424b0c9abdef8..250f48b7e711b 100644
--- a/pandas/tests/scalar/timestamp/test_timezones.py
+++ b/pandas/tests/scalar/timestamp/test_timezones.py
@@ -306,15 +306,14 @@ def test_astimezone(self, tzstr):
 
     @td.skip_if_windows
     def test_tz_convert_utc_with_system_utc(self):
-        from pandas._libs.tslibs.timezones import maybe_get_tz
 
         # from system utc to real utc
-        ts = Timestamp("2001-01-05 11:56", tz=maybe_get_tz("dateutil/UTC"))
+        ts = Timestamp("2001-01-05 11:56", tz=timezones.maybe_get_tz("dateutil/UTC"))
         # check that the time hasn't changed.
         assert ts == ts.tz_convert(dateutil.tz.tzutc())
 
         # from system utc to real utc
-        ts = Timestamp("2001-01-05 11:56", tz=maybe_get_tz("dateutil/UTC"))
+        ts = Timestamp("2001-01-05 11:56", tz=timezones.maybe_get_tz("dateutil/UTC"))
         # check that the time hasn't changed.
         assert ts == ts.tz_convert(dateutil.tz.tzutc())