diff --git a/Week04/functions_dilek_celebi.py b/Week04/functions_dilek_celebi.py
new file mode 100644
index 00000000..96b2a704
--- /dev/null
+++ b/Week04/functions_dilek_celebi.py
@@ -0,0 +1,39 @@
+# custom_power
+custom_power = lambda x=0, e=1: x ** e
+
+# custom_equation
+def custom_equation(
+    x: int = 0,
+    y: int = 0,
+    a: int = 1,
+    b: int = 1,
+    *,
+    c: int = 1
+) -> float:
+    """
+    Computes the equation (x^a + y^b) / c with specified parameters.
+    
+    :param x: First number, default is 0
+    :param y: Second number, default is 0
+    :param a: Power for x, default is 1
+    :param b: Power for y, default is 1
+    :param c: Divisor, default is 1, keyword-only
+    :return: Result of the calculation as a float
+    """
+    return (x ** a + y ** b) / c
+
+# fn_w_counter
+def fn_w_counter():
+    """
+    Tracks the total number of calls to this function and counts calls by each caller.
+
+    :return: A tuple with the total call count and a dictionary of caller names with their counts.
+    """
+    fn_w_counter.call_count += 1
+    caller = fn_w_counter.__globals__['__name__']
+    fn_w_counter.caller_counts[caller] = fn_w_counter.caller_counts.get(caller, 0) + 1
+    return fn_w_counter.call_count, fn_w_counter.caller_counts
+
+# Initialize tracking variables for fn_w_counter
+fn_w_counter.call_count = 0
+fn_w_counter.caller_counts = {}