title: TypeError: string indices must be integers -python
body: <p>I am using <code>pubmed_lookup</code> package in python, for some reasons, I got an error:</p>
  
  <pre><code>TypeError: string indices must be integers ;
  </code></pre>
  
  <p>and I cannot see what's wrong. I haven't got the foggiest idea about this error!　　　</p>
  
  <pre><code>with open ('file location','r') as f:
      urls =[line.strip() for line in f]
  
  
  lookup = [ ]
  for url in urls:
          lookup.append (PubMedLookup(url,email))
  i = 0
  while True:
      publication = Publication(lookup[i])
      print(
          """
  JOURNAL:\n{journal}\n
  """
          .format(**{
              'journal':publication.journal,
              }))
      i +=1
      if i &gt;3:
          break
  </code></pre>
  
  <p>My file format is as follows. <br/></p>
  
  <p><a href="http://www.ncbi.nlm.nih.gov/pubmed/28483699" rel="nofollow noreferrer">http://www.ncbi.nlm.nih.gov/pubmed/28483699</a>   <br/>
  <a href="http://www.ncbi.nlm.nih.gov/pubmed/26318800" rel="nofollow noreferrer">http://www.ncbi.nlm.nih.gov/pubmed/26318800</a>   <br/>
  <a href="http://www.ncbi.nlm.nih.gov/pubmed/28766011" rel="nofollow noreferrer">http://www.ncbi.nlm.nih.gov/pubmed/28766011</a>   <br/></p>
  
  <p>Thanks a lot!!!</p>
  
  <p>The error statement might be this: <br/>
  publication  = Publication(lookup[i])</p>