title: Appending values to dictionary in Python
body: <p>I have a dictionary to which I want to append to each drug, a list of numbers. Like this:</p>
  
  <pre><code>append(0), append(1234), append(123), etc.
  
  def make_drug_dictionary(data):
      drug_dictionary={'MORPHINE':[],
                       'OXYCODONE':[],
                       'OXYMORPHONE':[],
                       'METHADONE':[],
                       'BUPRENORPHINE':[],
                       'HYDROMORPHONE':[],
                       'CODEINE':[],
                       'HYDROCODONE':[]}
      prev = None
      for row in data:
          if prev is None or prev==row[11]:
              drug_dictionary.append[row[11][]
      return drug_dictionary
  </code></pre>
  
  <p>I later want to be able to access the entirr set of entries in, for example, <code>'MORPHINE'</code>.</p>
  
  <ol>
  <li>How do I append a number into the drug_dictionary?</li>
  <li>How do I later traverse through each entry?</li>
  </ol>