title: Beautifulsoup can't extract src attribute from img tag
body: <p>Here is my code:</p>
  
  <pre><code>html = '''&lt;img onload='javascript:if(this.width&gt;950) this.width=950'
  src="http://ww4.sinaimg.cn/mw600/c3107d40jw1e3rt4509j.jpg"&gt;'''
  soup = BeautifulSoup(html)
  imgs = soup.findAll('img')
  
  print imgs[0].attrs
  </code></pre>
  
  <p>It will print <code>[(u'onload', u'javascript:if(this.width&gt;950) this.width=950')]</code></p>
  
  <p>So where is the <code>src</code> attribute?</p>
  
  <p>If I replace html by something like <code>html = '''&lt;img src="/image/fluffybunny.jpg" title="Harvey the bunny" alt="a cute little fluffy bunny" /&gt;'''</code></p>
  
  <p>I get correct results as <code>[(u'src', u'/image/fluffybunny.jpg'), (u'title', u'Harvey the bunny'), (u'alt', u'a cute little fluffy bunny')]</code></p>
  
  <p>I am quite new to HTML and beautifulsoup. Am I missing some knowledge? Thanks for any ideas.</p>