title: Python 3 Flask - 404 Page Not Found Error
body: <p>I'm new to Flask and followed <a href="https://www.youtube.com/watch?v=uqr-e-dkkNI&amp;t=346s" rel="nofollow noreferrer">this walkthrough</a> but am running into an issue. I want a user to be able to input text in a text field on the index.html page, hit the submit button, and take them to trader.html page. I'm running into a 404 Page Not Found error with my below code when the button is hit, but I'm not sure where I'm going wrong? The URL bar shows the correct /trader.html address after the button is hit, but getting the 404 error page.</p>
  
  <p>The 2 answers I found on SO for similar issues didn't work here as they mentioned that there needed to be a separate app.route to navigate them to the correct second page, but I already have that set up in my code???</p>
  
  <p>app.py</p>
  
  <pre><code>from flask import Flask, request, jsonify, render_template
  
  @app.route('/', methods = ['GET'])
  def hello():
      return render_template('index.html')
  
  @app.route('/trader', methods = ['POST'])
  def trader_page():
      the_stock=request.form['inputted_stock']
      return render_template('trader.html')
  </code></pre>
  
  <p>index.html</p>
  
  <pre><code>&lt;h1 style="color: #4485b8;"&gt;Welcome to the live stock trader!&lt;/h1&gt;
  
  &lt;p&gt;Select a stock ticker below to begin testing:&lt;/p&gt;
  &lt;form action="/trader.html" method="POST"&gt;
  &lt;option value="AAPL"&gt;AAPL&lt;/option&gt;
  &lt;option value="ABBV"&gt;ABBV&lt;/option&gt;
  &lt;option value="ABT"&gt;ABT&lt;/option&gt;
  &lt;/select&gt;&lt;br /&gt;&lt;br /&gt; 
  
  &lt;table&gt;
  &lt;tr&gt;&lt;td&gt;Enter Stock Ticker&lt;/td&gt;&lt;td&gt;&lt;input type="text" name="inputted_stock" /&gt;&lt;/td&gt;&lt;/tr&gt;
  &lt;/table&gt;
  
  &lt;input type="submit" value="Submit"/&gt;&lt;/form&gt;
  &lt;p&gt;&lt;/p&gt;
  &lt;table class="editorDemoTable" style="vertical-align: top;"&gt;
  &lt;thead&gt;&lt;/thead&gt;
  &lt;/table&gt;
  </code></pre>
  
  <p>trader.html</p>
  
  <pre><code>&lt;h1 style="color: #4485b8;"&gt;{{inputted_stock}} trader!&lt;/h1&gt;
  &lt;p&gt;Begin testing...&lt;/p&gt;
  </code></pre>