title: SyntaxError: Name 's' is used prior to global declaration in Python/Flask code
body: <p>The goal of my code is to place it into two EC2 instances which is then connected to a load balancer to distribute requests between the two instances. </p>
  
  <p>This is my code which I am first trying to test in my local before I test it in the EC2 instances and then ultimately test everything with the load balancer as well.</p>
  
  <pre><code>from flask import Flask,request,session
  ##global s
  s = 0
  app = Flask(__name__)
  
  @app.route("/", methods=["GET","POST"])
  def disp():
      if request.method == "GET":
          global s
          s = 0 
          return str(s)
      if request.method == "POST":
          global s
          s = request.json["num"]
          return str(s)
  
  if __name__ =="__main__":
      app.run()
      ##app.run('0.0.0.0', port=80)
  </code></pre>
  
  <p>The error that returns when I run locally is SyntaxError: Name 's' is used prior to global declaration. I tried removing the s=0 after the import line but the error still persists.</p>