diff --git a/Week02/types_yigithan_erken.py b/Week02/types_yigithan_erken.py
new file mode 100644
index 000000000..f64e80967
--- /dev/null
+++ b/Week02/types_yigithan_erken.py
@@ -0,0 +1,4 @@
+my_int = 1903
+my_float = 19.03
+my_bool = True
+my_complex = 190 + 3j
\ No newline at end of file
diff --git a/Week03/pyramid_yigithan_erken.py b/Week03/pyramid_yigithan_erken.py
new file mode 100644
index 000000000..dae611cdb
--- /dev/null
+++ b/Week03/pyramid_yigithan_erken.py
@@ -0,0 +1,8 @@
+def calculate_pyramid_height(number_of_blocks):
+    height = 0
+    used = 1
+    while number_of_blocks >= used:
+        number_of_blocks -= used
+        height += 1
+        used += 1
+    return height
diff --git a/Week03/sequences_yigithan_erken.py b/Week03/sequences_yigithan_erken.py
new file mode 100644
index 000000000..6b9827b5a
--- /dev/null
+++ b/Week03/sequences_yigithan_erken.py
@@ -0,0 +1,17 @@
+def remove_duplicates(seq: list) -> list:
+    return list(set(seq))
+
+def list_counts(seq: list) -> dict:
+    counts = {}
+    for item in seq:
+        if item in counts:
+            counts[item] += 1
+        else:
+            counts[item] = 1
+    return counts
+
+def reverse_dict(d: dict) -> dict:
+    reversed_dict = {}
+    for key, value in d.items():
+        reversed_dict[value] = key
+    return reversed_dict
\ No newline at end of file
diff --git a/Week04/decorators_yigithan_erken.py b/Week04/decorators_yigithan_erken.py
new file mode 100644
index 000000000..67ba79793
--- /dev/null
+++ b/Week04/decorators_yigithan_erken.py
@@ -0,0 +1,31 @@
+import time
+import tracemalloc
+
+def performance(func):
+
+    def wrapper(*args, **kwargs):
+        
+        tracemalloc.start()
+        start = time.perf_counter()
+        start_mem = tracemalloc.get_traced_memory()[0]
+        tracemalloc.reset_peak()
+
+        try:
+            result = func(*args, **kwargs)
+        
+        finally:
+            end = time.perf_counter()
+            current, peak = tracemalloc.get_traced_memory()
+            
+            performance.counter += 1
+            performance.total_time += end - start
+            performance.total_mem += peak - start_mem
+            
+            tracemalloc.stop()
+
+        return result
+    return wrapper
+
+performance.counter = 0
+performance.total_time = 0
+performance.total_mem = 0
\ No newline at end of file
diff --git a/Week04/functions_yigithan_erken.py b/Week04/functions_yigithan_erken.py
new file mode 100644
index 000000000..33df1315b
--- /dev/null
+++ b/Week04/functions_yigithan_erken.py
@@ -0,0 +1,33 @@
+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:
+    """
+    Calculates a custom equation.
+
+    :param x: Positional-only integer, defaults to 0.
+    :param y: Positional-only integer, defaults to 0.
+    :param a: Positional-or-keyword integer, defaults to 1.
+    :param b: Positional-or-keyword integer, defaults to 1.
+    :param c: Keyword-only integer, defaults to 1.
+    :return: The result of (x**a + y**b) / c as float.
+    """
+    if not all(isinstance(val, int) for val in (x, y, a, b, c)):
+        raise TypeError("Arguments must be integers.")
+        
+    return float((x**a + y**b) / c)
+
+def fn_w_counter() -> (int, dict[str, int]):
+    if not hasattr(fn_w_counter, "total_calls"):
+        fn_w_counter.total_calls = 0
+        fn_w_counter.caller_counts = {}
+    
+    caller_name = __name__
+
+    fn_w_counter.total_calls += 1
+    
+    if caller_name in fn_w_counter.caller_counts:
+        fn_w_counter.caller_counts[caller_name] += 1
+    else:
+        fn_w_counter.caller_counts[caller_name] = 1
+
+    return (fn_w_counter.total_calls, fn_w_counter.caller_counts)
\ No newline at end of file
diff --git a/Week05/emails_yigithan_erken.py b/Week05/emails_yigithan_erken.py
new file mode 100644
index 000000000..e67f2d739
--- /dev/null
+++ b/Week05/emails_yigithan_erken.py
@@ -0,0 +1,27 @@
+class Emails(list):
+    def __init__(self, initial_emails=None):
+        super().__init__()
+        self.data = self
+        if initial_emails is not None:
+            self.validate(initial_emails)
+
+    def validate(self, emails_to_check):
+        for item in emails_to_check:
+            if not isinstance(item, str):
+                raise ValueError("List can only contain strings")
+            
+            if "@" not in item:
+                raise ValueError("Invalid email format")
+                
+            domain_part = item.split("@")[1]
+            if "." not in domain_part:
+                raise ValueError("Invalid email format")
+            
+            if item not in self:
+                self.append(item)
+
+    def __repr__(self):
+        return f"Emails({super().__repr__()})"
+
+    def __str__(self):
+        return super().__str__()
\ No newline at end of file