missing numbers problem in python

Algorithms/MissingNumbers/Python/ggedler/problem.py

+def missingNumbers(arr, brr):
+  dicA = convertArrToDic(arr)
+  dicB = convertArrToDic(brr)
+    
+  missingNums = []
+  for key in dicB.keys():
+   if (not key in  dicA) or dicA[key] != dicB[key]:
+     missingNums.append(key)
+    
+  return missingNums
+
+
+def convertArrToDic(arr):
+  dic = {}
+  for i in arr:
+    addToDic(dic, i)
+
+  return dic
+
+
+def addToDic(dic, i):
+  if not i in dic:
+    dic[i] = 1
+    return
+  
+  dic[i] = dic[i] + 1
+    
+
+
+arr = [11, 4, 11, 7, 13, 4, 12, 11, 10, 14]
+print("input array A: ")
+print(arr)
+brr = [11, 4, 11, 7, 3, 7, 10, 13, 4, 8, 12, 11, 10, 14, 12]
+print("input array B: ")
+print(brr)
+
+print("missing numbers: ")
+print(missingNumbers(arr,brr))