diff --git a/Week04/functions_ayberk_baycin.py b/Week04/functions_ayberk_baycin.py
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+++ b/Week04/functions_ayberk_baycin.py
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+import inspect
+
+# 1. custom_power: Lambda function with positional-only and default values
+# '/' işareti öncesindekilerin sadece pozisyonla (x=0 gibi değil, sadece 0) girilebileceğini belirtir.
+custom_power = lambda x=0, /, e=1: x ** e
+
+# 2. custom_equation: Complex function with specific parameter rules
+def custom_equation(x: int = 0, y: int = 0, /, a: int = 1, b: int = 1, *, c: int = 1) -> float:
+    """
+    Calculates the result of a custom mathematical equation.
+
+    :param x: Positional-only base for first power
+    :param y: Positional-only base for second power
+    :param a: Exponent for x
+    :param b: Exponent for y
+    :param c: Keyword-only divisor
+    :return: The result of (x**a + y**b) / c as a float
+    """
+    return float((x**a + y**b) / c)
+
+# 3. fn_w_counter: Function that counts its callers
+# Global değişkenler kullanarak çağrı sayılarını takip ediyoruz
+_total_calls = 0
+_caller_counts = {}
+
+def fn_w_counter() -> tuple[int, dict[str, int]]:
+    global _total_calls
+    _total_calls += 1
+    
+    # Bir üst seviyedeki (çağıran) fonksiyonun ismini alır
+    frame = inspect.currentframe().f_back
+    caller_name = frame.f_globals.get('__name__', '__main__')
+    
+    _caller_counts[caller_name] = _caller_counts.get(caller_name, 0) + 1
+    
+    return _total_calls, _caller_counts