title: Catch proxy errors on requests python
body: <p>I'm new on python so I'm having some trouble. I'm trying to build a tool that posts data to an external server with proxy. I have it working, but the problem is I don't know how to catch the proxy connection error and print something else. The code I wrote is: </p>
  
  <pre><code>import requests
  from bs4 import BeautifulSoup
  
  headers = {
      "User-Agent": "User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.11) Gecko/2009060215 Firefox/3.0.11",
      "Content-Type": "application/json"
  }
  proxies = { 
      "https": "https://244.324.324.32:8081",
  }
  data = {"test": "test"}
  r = requests.post("https://example.com/page", proxies=proxies, json=data, headers=headers)
  print(r.text)
  </code></pre>
  
  <p>How can I print, for example "Proxy Connection Error", when the proxy is dead (not connecting/working) or something like this. This is my first time using python so I'm having trouble.</p>
  
  <p>Thank You</p>