Implement utility functions for list and dict operations

Added functions to remove duplicates, count occurrences, and reverse dictionaries.

Author: sinemtanriver

Week03/sequences_sinem_tanriver.py

@@ -0,0 +1,28 @@
+from collections import Counter
+
+
+def remove_duplicates(seq: list) -> list:
+    """
+    This function removes duplicates from a list.
+    """
+    seen = set()
+    unique = []
+    for item in seq:
+        if item not in seen:
+            seen.add(item)
+            unique.append(item)
+    return unique
+
+
+def list_counts(seq: list) -> dict:
+    """
+    This function counts the number of occurrences of each item in a list.
+    """
+    return dict(Counter(seq))
+
+
+def reverse_dict(d: dict) -> dict:
+    """
+    This function reverses the keys and values of a dictionary.
+    """
+    return dict(zip(d.values(), d.keys()))