diff --git a/Week04/decorators_cemil_koca.py b/Week04/decorators_cemil_koca.py
new file mode 100644
index 00000000..bbb1fa96
--- /dev/null
+++ b/Week04/decorators_cemil_koca.py
@@ -0,0 +1,25 @@
+import time
+import tracemalloc
+
+def performance(fn):
+    def _performance(*args, **kwargs):  # wraps yok, düz wrapper
+        performance.counter += 1
+
+        tracemalloc.start()
+        start = time.perf_counter()
+
+        result = fn(*args, **kwargs)
+
+        elapsed = time.perf_counter() - start
+        _, peak = tracemalloc.get_traced_memory()
+        tracemalloc.stop()
+
+        performance.total_time += elapsed
+        performance.total_mem += peak
+
+        return result
+    return _performance
+
+performance.counter = 0
+performance.total_time = 0
+performance.total_mem = 0
\ No newline at end of file
diff --git a/Week04/functions_cemil_koca.py b/Week04/functions_cemil_koca.py
new file mode 100644
index 00000000..065e06ad
--- /dev/null
+++ b/Week04/functions_cemil_koca.py
@@ -0,0 +1,35 @@
+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:
+    """Calculate a custom equation.
+
+    :param x: Base value 1.
+    :type x: int
+    :param y: Base value 2.
+    :type y: int
+    :param a: Exponent for x.
+    :type a: int
+    :param b: Exponent for y.
+    :type b: int
+    :param c: Divisor.
+    :type c: int
+    :return: Result of (x**a + y**b) / c.
+    :rtype: 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 (x**a + y**b) / c
+
+
+def fn_w_counter() -> (int, dict[str, int]):
+    """Count function calls with caller information."""
+    fn_w_counter.total += 1
+    caller_name = __name__
+    fn_w_counter.callers[caller_name] = fn_w_counter.callers.get(caller_name, 0) + 1
+    return (fn_w_counter.total, dict(fn_w_counter.callers))
+
+
+fn_w_counter.total = 0
+fn_w_counter.callers = {}
diff --git a/Week05/awaitme_cemil_koca.py b/Week05/awaitme_cemil_koca.py
new file mode 100644
index 00000000..6a2ecb10
--- /dev/null
+++ b/Week05/awaitme_cemil_koca.py
@@ -0,0 +1,7 @@
+def awaitme(fn):
+    async def _wrapper(*args, **kwargs):
+        return fn(*args, **kwargs)
+    _wrapper.__name__ = fn.__name__
+    _wrapper.__doc__ = fn.__doc__
+    _wrapper.__annotations__ = fn.__annotations__
+    return _wrapper
\ No newline at end of file
diff --git a/Week06/timer_cemil_koca.py b/Week06/timer_cemil_koca.py
new file mode 100644
index 00000000..3f13f670
--- /dev/null
+++ b/Week06/timer_cemil_koca.py
@@ -0,0 +1,13 @@
+import time
+
+class Timer:
+    def __init__(self):
+        self.start_time = None
+        self.end_time = None
+
+    def __enter__(self):
+        self.start_time = time.time()
+        return self
+
+    def __exit__(self, exc_type, exc_val, exc_tb):
+        self.end_time = time.time()
\ No newline at end of file
diff --git a/Week07/threaded_cemil_koca.py b/Week07/threaded_cemil_koca.py
new file mode 100644
index 00000000..c51f0b41
--- /dev/null
+++ b/Week07/threaded_cemil_koca.py
@@ -0,0 +1,44 @@
+import threading
+import random
+
+def threaded(n):
+    def decorator(func):
+        def wrapper(*args, **kwargs):
+            threads = [threading.Thread(target=func, args=args, kwargs=kwargs) for _ in range(n)]
+            for t in threads:
+                t.start()
+            for t in threads:
+                t.join()
+        return wrapper
+    return decorator
+
+total_points = 0
+inside_circle = 0
+lock = threading.Lock()
+
+NUM_POINTS_PER_THREAD = 100000
+NUM_THREADS = 4
+
+@threaded(NUM_THREADS)
+def estimate_pi():
+    global total_points, inside_circle
+    local_total = 0
+    local_inside = 0
+
+    for _ in range(NUM_POINTS_PER_THREAD):
+        x = random.uniform(-1, 1)
+        y = random.uniform(-1, 1)
+        if x * x + y * y <= 1:
+            local_inside += 1
+        local_total += 1
+
+    with lock:
+        total_points += local_total
+        inside_circle += local_inside
+
+if __name__ == "__main__":
+    estimate_pi()
+    pi_estimate = 4 * inside_circle / total_points
+    print(f"Total points: {total_points}")
+    print(f"Points inside circle: {inside_circle}")
+    print(f"Estimated Pi: {pi_estimate}")
\ No newline at end of file