title: BeautifulSoup: get_text() returns empty string from bs4 Tag
body: <p>I am trying to extract information from <a href="https://www.theguardian.com/politics/2019/oct/20/boris-johnson-could-be-held-in-contempt-of-court-over-brexit-letter" rel="nofollow noreferrer">this news page</a>.</p>
  
  <p>First I parse the page:</p>
  
  <pre><code>import requests
  from bs4 import BeautifulSoup
  page = requests.get("https://www.theguardian.com/politics/2019/oct/20/boris-johnson-could-be-held-in-contempt-of-court-over-brexit-letter")
  soup = BeautifulSoup(page.content, 'html.parser')
  </code></pre>
  
  <p>Then I start with the title:</p>
  
  <pre><code>title = soup.find('meta', property="og:title")
  </code></pre>
  
  <p>and if I print it, I get:</p>
  
  <pre><code>&lt;meta content="Boris Johnson could be held in contempt of court over Brexit letter" property="og:title"/&gt;
  </code></pre>
  
  <p>However, when I run <code>title.get_text()</code>, the outcome is an empty string: <code>''</code></p>
  
  <p>Where is my mistake?</p>