diff --git a/Week04/functions_zeynepnur_erten.py b/Week04/functions_zeynepnur_erten.py
new file mode 100644
index 00000000..0cfc474e
--- /dev/null
+++ b/Week04/functions_zeynepnur_erten.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 returns the result of an operation based on the specified base and exponent values.
+
+   :param x: First base value
+   :param y: Second base value
+   :param a: First exponent value
+   :param b: Second exponent value
+   :param c: Divisor value
+   :return: (x*a + y*b)/c
+  """
+  return (x**a + y**b)/c
+
+
+def fn_w_counter() -> (int, dict[str, int]):
+    if not hasattr(fn_w_counter, "calls"):
+        fn_w_counter.calls = 0
+    
+    fn_w_counter.calls += 1
+    
+    return fn_w_counter.calls, {__name__: fn_w_counter.calls}
+
+  
+
+