如何检查字符串是否只包含1和0？

import re

def check_binary_string(string):
    pattern = "^[01]+$"
    if re.match(pattern, string):
        return True
    else:
        return False

curl -X POST "https://scf.tencentcloudapi.com" \
  -H "Content-Type: application/json" \
  -d '{
    "Action": "Invoke",
    "Version": "2018-04-16",
    "FunctionName": "check_binary_string",
    "Handler": "index.main_handler",
    "Region": "ap-guangzhou",
    "SecretId": "your-secret-id",
    "SecretKey": "your-secret-key",
    "Event": {
      "string": "101010"
    }
  }'

from flask import Flask, request, jsonify

app = Flask(__name__)

@app.route("/check", methods=["POST"])
def check_binary_string():
    string = request.json.get("string")
    for char in string:
        if char != "0" and char != "1":
            return jsonify({"result": False})
    return jsonify({"result": True})

if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5000)

curl -X POST "http://your-cvm-ip:5000/check" \
  -H "Content-Type: application/json" \
  -d '{
    "string": "101010"
  }'