title: Getting a list of POS tags only from the tuples of (word,pos_tag)
body: <p>I have a list of list of sentences, tokenized by words and then pos tagged so the results is obviously is a list with elements:</p>
  
  <pre><code>[(w1,pos_tag1)(w2,pos_tag2)]
  [(w3,pos_tag3),(w4,pos_tag4),(w5,pos_tag5)]
  [(w6,pos_tag6),(w7,pos_tag7)]
  </code></pre>
  
  <p>I need to get a list of pos_tags only in the same order they happen in all sentences.What I tried was a iteration over the list </p>
  
  <p>tags = [x[1] for x in element in list]</p>
  
  <p>but this does not work.How can I have all tags in these lists?</p>
  
  <p>thanks</p>