title: Update all matching keys in list of dictionaries with value in Python
body: <pre><code>key = 'take'
  val = 5
  
  dicts = [
      OrderedDict([
          (u'rt', 0), 
          (u'janoameezy', 0), 
          (u'calum', 0), 
          (u'is', 0), 
          (u'me', 0), 
          (u'whenever', 0), 
          (u'i', 0), 
          (u'take', 0), 
          (u'a', 0), 
          (u'selfie', 0), 
          (u'http', 0), 
          (u't', 0), 
          (u'co', 0), 
          (u'sxn68vta2a', 0)
      ]), 
      OrderedDict([
          (u'relax', 0), 
          (u'and', 0), 
          (u'take', 0), 
          (u'notes', 0), 
          (u'while', 0), 
          (u'i', 0), 
          (u'tokes', 0), 
          (u'of', 0), 
          (u'the', 0), 
          (u'marijuana', 0), 
          (u'smoke', 0)
      ])
  ]
  </code></pre>
  
  <p>How can I replace all instances of key with val?</p>