diff --git a/tests/test_functions.py b/tests/test_functions.py
index 958b11335..8af6e8086 100644
--- a/tests/test_functions.py
+++ b/tests/test_functions.py
@@ -32,19 +32,18 @@
         ("empty list", [], False),
     ],
 )
+
 def test_functions_diff(test_description, given, expected):
     assert (
         functions.diff(given) == expected
     ), f"{test_description}: Expected {given} to return {expected}"
 
-
 def test_keep_len_function():
     """
     Test the len function
     """
     assert functions.len([1, 2, 3]) == 3
 
-
 def test_keep_all_function():
     """
     Test the all function
@@ -52,7 +51,6 @@ def test_keep_all_function():
     assert functions.all([1, 1, 1]) == True
     assert functions.all([1, 1, 0]) == False
 
-
 def test_keep_diff_function():
     """
     Test the diff function
@@ -60,7 +58,6 @@ def test_keep_diff_function():
     assert functions.diff([1, 1, 1]) == False
     assert functions.diff([1, 1, 0]) == True
 
-
 def test_keep_split_function():
     """
     Test the split function
@@ -68,6 +65,17 @@ def test_keep_split_function():
     assert functions.split("a,b,c", ",") == ["a", "b", "c"]
     assert functions.split("a|b|c", "|") == ["a", "b", "c"]
 
+def test_keep_uppercase_function():
+    """
+    Test the uppercase function
+    """
+    assert functions.uppercase("a") == "A"
+
+def test_keep_lowercase_function():
+    """
+    Test the lowercase function
+    """
+    assert functions.lowercase("A") == "a"
 
 def test_keep_strip_function():
     """
@@ -75,13 +83,17 @@ def test_keep_strip_function():
     """
     assert functions.strip("  a  ") == "a"
 
-
 def test_keep_first_function():
     """
     Test the first function
     """
     assert functions.first([1, 2, 3]) == 1
 
+def test_keep_last_function():
+    """
+    Test the last function
+    """
+    assert functions.last([1, 2, 3]) == 3
 
 def test_keep_utcnow_function():
     """
@@ -91,7 +103,6 @@ def test_keep_utcnow_function():
     assert isinstance(dt.tzinfo, type(datetime.timezone.utc))
     assert isinstance(dt, datetime.datetime)
 
-
 def test_keep_to_utc_function():
     """
     Test the to_utc function
@@ -103,7 +114,6 @@ def test_keep_to_utc_function():
     now_utc = functions.to_utc(now)
     assert now_utc.tzinfo == pytz.utc
 
-
 def test_keep_datetime_compare_function():
     """
     Test the datetime_compare function
@@ -114,7 +124,6 @@ def test_keep_datetime_compare_function():
     assert int(functions.datetime_compare(dt2, dt1)) == 1
     assert int(functions.datetime_compare(dt1, dt1)) == 0
 
-
 def test_keep_encode_function():
     """
     Test the encode function