title: Python csv module throws "Error: sequence expected" at writer.writerow
body: <p>I am attempting to run the following code in Python, and am getting the error:</p>
  
  <pre><code> csv.Error: sequence expected
  </code></pre>
  
  <p>Does anyone have any idea what is wrong with my code? (The file was previously imported into the program).</p>
  
  <pre><code>import csv
  file = open('/home/btoms/Desktop/TomsBen/2000/01/01/20000101acme.mts', 'r')
  
  variables = []
  
  file.readline() #Skip a line
  file.readline() 
  file.readline() #Skip another line
  
  for line in file:
      tmp = line.split()
      tmp_STID = str(tmp[0])
      tmp_T = float(tmp[4]) 
      tmp_RH = float(tmp[3])
      tmp_Times = float(tmp[2])
      variables.append(tmp_STID)
      variables.append(tmp_Times)
      variables.append(tmp_T)
      variables.append(tmp_RH)
  
  
      if tmp_T &lt; 6.2 and tmp_RH &gt; 60.0: 
      dataCSV = open('ProgramCheck.csv', 'w') 
      writer = csv.writer(dataCSV, dialect='excel')
      writer.writerow(['Station ID', 'Time', 'Temperature' , 'Relative Humidity']) 
  
      for values in variables:
          writer.writerow(values)
      else:
              pass
      file.close()
  </code></pre>
  
  <p>The error comes up as:</p>
  
  <pre><code>    Traceback (most recent call last):
        File "checkcsv.py", line 30, in &lt;module&gt;
          writer.writerow(values)
      _csv.Error: sequence expected
  </code></pre>