0001. Add python v2. Making use of the dictionary property.

problems/0001.两数之和.md

@@ -118,6 +118,18 @@ class Solution:
                 return [records[target - val], idx] # 如果存在就返回字典记录索引和当前索引
 ```
 
+Python (v2):
+
+```python
+class Solution:
+    def twoSum(self, nums: List[int], target: int) -> List[int]:
+        rec = {}
+        for i in range(len(nums)):
+            rest = target - nums[i]
+            # Use get to get the index of the data, making use of one of the dictionary properties.
+            if rec.get(rest, None) is not None: return [rec[rest], i]
+            rec[nums[i]] = i
+```
 
 Go：