diff --git a/Week04/functions_abdulsamet_kucuk.py b/Week04/functions_abdulsamet_kucuk.py
new file mode 100644
index 00000000..4ff31b16
--- /dev/null
+++ b/Week04/functions_abdulsamet_kucuk.py
@@ -0,0 +1,30 @@
+custom_power = lambda x=0, /, e=1: x**e
+
+def custom_equation(x: int = 0, y: int = 0, /, a: int = 1, b: int = 1, *, c: int = 1) -> float:
+    """
+    Calculates the custom equation (x**a + y**b) / c.
+
+    :param x: The first base value (positional-only).
+    :param y: The second base value (positional-only).
+    :param a: The first exponent value (positional-or-keyword).
+    :param b: The second exponent value (positional-or-keyword).
+    :param c: The divisor (keyword-only).
+    :return: The result of the custom equation as a float.
+    """
+    for param in (x, y, a, b, c):
+        if not isinstance(param, int) or isinstance(param, bool):
+            raise TypeError("All parameters must be integers.")
+
+    return float((x**a + y**b) / c)
+
+def fn_w_counter() -> (int, dict[str, int]):
+    if not hasattr(fn_w_counter, "total_calls"):
+        fn_w_counter.total_calls = 0
+        fn_w_counter.callers = {}
+
+    caller_name = __name__
+
+    fn_w_counter.total_calls += 1
+    fn_w_counter.callers[caller_name] = fn_w_counter.callers.get(caller_name, 0) + 1
+
+    return fn_w_counter.total_calls, fn_w_counter.callers