Add functions for removing duplicates and counting items

Week03/sequences_aysegul_yildiz.py

@@ -0,0 +1,23 @@
+def remove_duplicates(seq):
+    sonuc = []
+    for oge in seq:
+        if oge not in sonuc:
+            sonuc.append(oge)
+    return sonuc
+
+
+def list_counts(seq):
+    sayimlar = {}
+    for oge in seq:
+        sayimlar[oge] = sayimlar.get(oge, 0) + 1
+    return sayimlar
+
+
+def reverse_dict(d):
+    ters = {}
+    for anahtar, deger in d.items():
+        if deger not in ters:
+            ters[deger] = [anahtar]
+        else:
+            ters[deger].append(anahtar)
+    return ters