diff --git a/beginner/sum-of-all-numbers-rosdyana.py b/beginner/sum-of-all-numbers-rosdyana.py
index 0eca840..8c8da4c 100644
--- a/beginner/sum-of-all-numbers-rosdyana.py
+++ b/beginner/sum-of-all-numbers-rosdyana.py
@@ -10,4 +10,4 @@ def sum_all(list_input):
     # start to sum it
     for i in range(firstnum, secondnum+1):
         result += i
-    return result
\ No newline at end of file
+    return result
diff --git a/beginner/sum_of_all_numbers_mikelane.py b/beginner/sum_of_all_numbers_mikelane.py
new file mode 100644
index 0000000..5b6178c
--- /dev/null
+++ b/beginner/sum_of_all_numbers_mikelane.py
@@ -0,0 +1,18 @@
+from typing import List
+
+
+def sum_all(list_input: List[int]) -> int:
+    """Challenge
+
+        - Write a function called sum_all() that takes a list of two numbers.
+        - Return the sum of those two numbers plus the sum of all the numbers between them.
+
+    Notes:
+        The lowest number will not always come first
+
+    >>> sum_all([1, 4])
+    10
+    >>> sum_all([4, 1])
+    10
+    """
+    return sum(range(min(list_input), max(list_input) + 1))