Created merge_sorted_lists and tests for that

functions/merge_sorted_lists.py

@@ -1,2 +1,4 @@
 def merge_sorted_lists(l1, l2):
-    pass
+    merged = l1 + l2
+
+    return sorted(merged)

tests/merge_sorted_lists_test.py

@@ -1,2 +1,38 @@
 import pytest
 from functions.merge_sorted_lists import merge_sorted_lists
+
+
+def test_for_1_and_2():
+    # Arrange
+    l1 = [1]
+    l2 = [2]
+
+    # Act
+    answer = merge_sorted_lists(l1, l2)
+
+    # Assert
+    assert answer == [1, 2]
+
+
+def test_for_2_and_1():
+    # Arrange
+    l1 = [2]
+    l2 = [1]
+
+    # Act
+    answer = merge_sorted_lists(l1, l2)
+
+    # Assert
+    assert answer == [1, 2]
+
+
+def test_for_1_2_3_and_4_5_6():
+    # Arrange
+    l1 = [1, 2, 3]
+    l2 = [4, 5, 6]
+
+    # Act
+    answer = merge_sorted_lists(l1, l2)
+
+    # Assert
+    assert answer == [1, 2, 3, 4, 5, 6]