update反转链表：添加python递归法的代码

problems/0206.翻转链表.md

@@ -142,7 +142,7 @@ class Solution {
 }
 ```
 
-Python：
+Python迭代法：
 ```python
 #双指针
 # Definition for singly-linked list.
@@ -163,6 +163,32 @@ class Solution:
         return pre
 ```
 
+Python递归法：
+
+```python
+# Definition for singly-linked list.
+# class ListNode:
+#     def __init__(self, val=0, next=None):
+#         self.val = val
+#         self.next = next
+class Solution:
+    def reverseList(self, head: ListNode) -> ListNode:
+        
+        def reverse(pre,cur):
+            if not cur:
+                return pre
+                
+            tmp = cur.next
+            cur.next = pre
+
+            return reverse(cur,tmp)
+        
+        return reverse(None,head)
+
+```
+
+
+
 Go：
 
 ```go