Change sum() to ndarray.sum()

Author: kotamatsuoka

pandas/core/algorithms.py

@@ -713,7 +713,7 @@ def value_counts(
             # handle Categorical and sparse,
             result = Series(values)._values.value_counts(dropna=dropna)
             result.name = name
-            counts = result._values
+            counts = result._values.to_numpy()
 
         else:
             keys, counts = _value_counts_arraylike(values, dropna)
@@ -724,7 +724,7 @@ def value_counts(
         result = result.sort_values(ascending=ascending)
 
     if normalize:
-        result = result / float(sum(counts))
+        result = result / float(counts.sum())
 
     return result