Add Python3 solution to README_EN.md

Author: yanglbme

solution/0700-0799/0772.Basic Calculator III/README_EN.md

@@ -71,7 +71,32 @@ tags:
 #### Python3
 
 ```python
-
+class Solution:
+    def calculate(self, s: str) -> int:
+        def dfs(q):
+            num, sign, stk = 0, "+", []
+            while q:
+                c = q.popleft()
+                if c.isdigit():
+                    num = num * 10 + int(c)
+                if c == "(":
+                    num = dfs(q)
+                if c in "+-*/)" or not q:
+                    match sign:
+                        case "+":
+                            stk.append(num)
+                        case "-":
+                            stk.append(-num)
+                        case "*":
+                            stk.append(stk.pop() * num)
+                        case "/":
+                            stk.append(int(stk.pop() / num))
+                    num, sign = 0, c
+                if c == ")":
+                    break
+            return sum(stk)
+
+        return dfs(deque(s))
 ```
 
 #### Java