diff --git a/Week01/info_cavit_can_key.py b/Week01/info_cavit_can_key.py
new file mode 100644
index 00000000..165fed5e
--- /dev/null
+++ b/Week01/info_cavit_can_key.py
@@ -0,0 +1,2 @@
+student_id = "230316030"
+full_name = "Cavit Can Key"
diff --git a/Week02/weighted_cavit_can_key.py b/Week02/weighted_cavit_can_key.py
new file mode 100644
index 00000000..ae89582c
--- /dev/null
+++ b/Week02/weighted_cavit_can_key.py
@@ -0,0 +1,9 @@
+import random
+
+
+def weighted_srs(data, n, weights, with_replacement=False):
+    if weights is not None:
+        return random.choices(data, weights=weights, k=n)
+    if with_replacement:
+        return random.choices(data, k=n)
+    return random.sample(data, n)
diff --git a/Week03/shifted_cavit_can_key.py b/Week03/shifted_cavit_can_key.py
new file mode 100644
index 00000000..316fb37c
--- /dev/null
+++ b/Week03/shifted_cavit_can_key.py
@@ -0,0 +1,6 @@
+def shifted(sample):
+    data = sorted(sample)
+    n = len(data)
+    mean = sum(data) / n
+    median = (data[(n - 1) // 2] + data[n // 2]) / 2
+    return abs(mean - median) / abs(mean) * 100 if mean else 0