title: python: how to make list with all lowercase?
body: <p>I am new to this whole python and the data mining.
  Let's say I have a list of string called data</p>
  
  <pre><code>data[0] = ['I want to make everything lowercase']
  data[1] = ['How Do I Do It']
  data[2] = ['With A Large DataSet']
  </code></pre>
  
  <p>and so on. My len(data) gives 50000.</p>
  
  <p>I have tried</p>
  
  <pre><code>{k.lower(): v for k, v in data.items()}
  </code></pre>
  
  <p>and it gives me error saying that 'list' object has no attribute 'items'.
  and I have also tried using .lower() and it is giving me the same AtrributeError.</p>
  
  <p>How do I recursively call the lower() function in all the data[:50000] to make all the of strings in the data to all lowercase?</p>
  
  <p>EDIT:</p>
  
  <p>For more details: I have a json file with datas such as:</p>
  
  <pre><code>{'review/a': 1.0, 'review/b':2.0, 'review/c':This IS the PART where I want to make all loWerCASE}
  </code></pre>
  
  <p>Then I call a function to get the specific reviews that I want to make all lower case to</p>
  
  <pre><code>def lowerCase(datum):
    feat = [datum['review/c']]
    return feat
  
  lowercase = [lowercase(d) for d in data]
  </code></pre>
  
  <p>Now that I have all the 'review/c' information in my lowercase list.</p>
  
  <p>I want to make all of that strings to lower case</p>