title: Python reading files in a directory
body: <p>I have a .csv with 3000 rows of data in 2 columns like this:</p>
  
  <pre><code>uc007ayl.1  ENSMUSG00000041439
  uc009mkn.1  ENSMUSG00000031708
  uc009mkn.1  ENSMUSG00000035491
  </code></pre>
  
  <p>In another folder I have a graphs with name like this:</p>
  
  <pre><code>uc007csg.1_nt_counts.txt
  uc007gjg.1_nt_counts.txt
  </code></pre>
  
  <p>You should notice those graphs have a name in the same format of my 1st column</p>
  
  <p>I am trying to use python to identify those rows that have a graph and print the name of 2nd column in a new .txt file</p>
  
  <p>These are the codes I have</p>
  
  <pre><code>import csv
  with open("C:/*my dir*/UCSC to Ensembl.csv", "r") as f:
  reader = csv.reader(f, delimiter = ',')
      for row in reader:
          print row[0]
  </code></pre>
  
  <p>But this as far as I can get and I am stuck.</p>