--- a
+++ b/model/utils.py
@@ -0,0 +1,22 @@
+def age_vocab(max_age, mon=1, symbol=None):
+    age2idx = {}
+    idx2age = {}
+    if symbol is None:
+        symbol = ['PAD', 'UNK']
+
+    for i in range(len(symbol)):
+        age2idx[str(symbol[i])] = i
+        idx2age[i] = str(symbol[i])
+
+    if mon == 12:
+        for i in range(max_age):
+            age2idx[str(i)] = len(symbol) + i
+            idx2age[len(symbol) + i] = str(i)
+    elif mon == 1:
+        for i in range(max_age * 12):
+            age2idx[str(i)] = len(symbol) + i
+            idx2age[len(symbol) + i] = str(i)
+    else:
+        age2idx = None
+        idx2age = None
+    return age2idx, idx2age
\ No newline at end of file