diff --git a/Week04/functions_mustafa_kilic.py b/Week04/functions_mustafa_kilic.py
new file mode 100644
index 00000000..37e9d111
--- /dev/null
+++ b/Week04/functions_mustafa_kilic.py
@@ -0,0 +1,29 @@
+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:
+    """
+    This function raises x to the power of a, y to the power of b, sums them, and then divides the result by c.
+
+    :param x: The positional-only integer base parameter for the equation , default is 0
+    :param y: The positional-only integer base parameter for the equation , default is 0
+    :param a: The positional-or-keyword integer exponent parameter for the equation , default is 1
+    :param b: The positional-or-keyword integer exponent parameter for the equation , default is 1
+    :param c: The keyword-only integer divisor parameter for the equation , default is 1
+    :return: The result of the calculation as a float and the equation is (x**a + y**b) / c
+    :rtype: float
+    """
+    return (x**a + y**b) / c
+
+
+def fn_w_counter() -> (int, dict[str, int]):
+    if not hasattr(fn_w_counter,'_call_counter'):
+        fn_w_counter._call_counter = 0
+        fn_w_counter._caller_dict = {}
+    caller = __name__
+    fn_w_counter._call_counter += 1
+    if caller in fn_w_counter._caller_dict:
+        fn_w_counter._caller_dict[caller] += 1
+    else:
+        fn_w_counter._caller_dict[caller] = 1
+    return fn_w_counter._call_counter,fn_w_counter._caller_dict